diff options
Diffstat (limited to 'Master/texmf-dist/source/generic/knuth/errata/errorlog.tex')
| -rw-r--r-- | Master/texmf-dist/source/generic/knuth/errata/errorlog.tex | 2924 |
1 files changed, 2924 insertions, 0 deletions
diff --git a/Master/texmf-dist/source/generic/knuth/errata/errorlog.tex b/Master/texmf-dist/source/generic/knuth/errata/errorlog.tex new file mode 100644 index 00000000000..dc4845c1c19 --- /dev/null +++ b/Master/texmf-dist/source/generic/knuth/errata/errorlog.tex @@ -0,0 +1,2924 @@ +% Appendix to the Errors of TeX paper (updated) +% Section numbers now adjusted to TeX 3.0 equivalents +% NB: tab marks are significant in this file, they signal continuation lines +%\magnification=\magstephalf +%\pageno=35 +\input logmac +* 10 Mar 1978 +L1. Rename a few external variables to make their first six letters unique. +D2. Initialize \\{escape_char} to $-1$, not 0 [it will be set to the + first character input]. @240 +L3. Fix bug: The test `$\\{id}<\O{200}$' was supposed to distinguish one-letter + identifiers from longer (packed) ones, but negative values of + \\{id} also pass this test. @356 +B4. Fix bug: I wrote `{\bf while} $\alpha\land(\beta\lor\gamma)$' when I meant + `{\bf while} $(\alpha\land\beta)\lor\gamma$'. @259 +R5. Initialize the input routines in |INITEX| [at this time a short, + separate program not under user control], in case errors occur. @1337 +E6. Don't initialize \\{mem} in |INITEX|, it wastes time. @164 +B7. Change `\\{new_line}' [which denotes a lexical scanning state] to + `\\{next_line}' [which denotes + \\{carriage_return} and \\{line_feed}] in print commands. +F8. Include additional test `$\\{mem}[p] \ne 0\; \land$' in \\{check_mem}. @168 +M9. Fix inconsistency between the \\{eq_level} conventions of \\{macro_def} and + \\{eq_define}. @277 +# About six hours of debugging time today. +# |INITEX| appears to work, + and the test routine got through \\{start_input}, + \\{chcode} [the \TeX78 command for assigning a \\{cat_code}], + \\{get_next}, and \\{back_input} the first time. +* 11 Mar 1978 +I10. Insert space before `|(|' on terminal when opening a new file. @537 +F11. Put `$p\gets \\{link}(p)$' into the loop of \\{show_token_list}, + so that it doesn't loop forever. @292 +L12. Shift the last item found by \\{scan_toks} into the \\{info} field. + [With |SAIL| all packing of fields was done by arithmetic operations, + not by the compiler.] @474 +B13\>12. Fix the previous bugfix: I shifted by the wrong amount. @474 +I14. Add a feature that prints a warning when the end of a file page occurs within + a macro definition or call. [System dependent.] @336 +# Unintended bugs in my test routine [a format intended eventually to typeset + {\sl The Art of Computer Programming\/}] helped check out the + error recovery mechanisms. + For example, I had `|\lft{#}|' instead of `|\lft{##}|' inside a macro, + and three cases of improper |{|~and~|}| nesting. +F15. Add the forgotten case `\\{set_font}:' to \\{eq_destroy}. @275 +C16. Change |\require| to |\input|. @376 +F17. Add code for the case $\\{cur_cmd}=0$ [later known as the case + `$\,t\ge\\{cs_token_flag}$'] when scanning a tokenlist. @357 +# That's the first ``big'' error I've spotted so far. +I18. Introduce a `|d|' option in the error routine, to facilitate debugging. @84 +L19. Assign a floating-point constant \\{ignore_depth} to \\{prev_depth}, + instead of assigning the integer constant \\{flag} + [since \\{prev_depth} is type \\{real} in \TeX78]. @215 +I20. Improve the readability and spacing of \\{show_node_list} output. @182,187 +F21. Set the variable $v$ before using the {\bf case} construction in + \\{show_node_list}, because there's one case where $v$ + didn't receive a value [as part of the field unpacking]. @182 +# About seven hours today. +* 12 Mar 1978 +# One hour to enter yesterday's corrections and recompile. +# At this point \TeX\ correctly located further unintended syntax errors + in |acphdr| [the test file]. +I22. Insert \\{debug_help} into \\{succumb}, giving a chance to look at memory + before the system dies. @93 +D23. Use \\{eq_destroy} wherever necessary in \\{unsave}. @283 +L24. Change `$t \gets (t-1)$ mod 8' to `$t \gets (t-1)$ land~7' in \\{id_name}, + since |SAIL| has $-1$~mod~$8 = -1$. [At this time, \\{id_name} is a + routine that unpacks control sequence names, according to a scheme + that will become obsolete after change \#422.] +S25. Remove the space that appears at end of paragraph. + (I hadn't anticipated that.) @816 +L26. Throw away unwanted \\{line_feed} after getting a \\{carriage_return} + in response to \\{in_chr_w} [a system routine for + input from the terminal]. @83 +B27. Delete spurious call to \\{flush_list} in \\{end_token_list}. @324 +# Why did I make such a silly mistake? +F28. Fix bug in \\{get_x_token}: I forgot to say `\\{macro_call}' (which is the + main point of that routine)! @380 +# While tracking that bug down, I found out incidentally that kerning is okay. +# Also \TeX\ correctly caught an error |0p| for |0pt|. +L29. Fix bug in \\{scan_spec} ({\bf while} instead of {\bf repeat}). @404 +M30. Make the table entries for |\hfill| and |\hskip| consistent with the + program conventions. @1058 +L31. Disable unforeseen coercion: When \\{scan_spec} put \\{hsize} on + \\{save_stack}, the value changed from \\{real} to \\{integer}. @645 +I32. Use `|*|' instead of `|-1.0|' for running dimensions + of rules in \\{show_node_list}. @176 +D33. Clear \\{mem}[\\{head}] to null in \\{push_nest} [in \TeX82, this + will be done by \\{get_avail}]. @216 +# A vrule link got clobbered because I forgot to do this. +I34. Translate ASCII control codes to special form when displaying them. @48,68 +# Ligatures work, but \\{show_node_list} showed them funny. +F35. Remember to clear parameters off \\{save_stack} in \\{package} routine. @1086 +# About eight hours today. +* 13 Mar 1978 +D36. Introduce a new variable \\{hang_first} [later the sign of \\{hang_after}]. @849 +E37\>36. Simplify the new code, realizing that if $\\{hang_indent}=0$ then + \\{hang_first} is irrelevant. @848 +# Time sharing is very slow today, so I'm mostly reading technical reports while + waiting\/ {\bf three hours} for compiler, editor, and loading routine. +# I'm not counting this as debugging time! +# (Came back in the evening.) +P38. Spruce up the comments in the \\{line_break} routine, which appears to be + almost working. @813 +D39. Rethink the setting of \\{best_line}; it's 1 too high in many cases. + [The final line of a paragraph was handled in a treacherous way.] @874 +D40. Compute proper initialization for + \\{prev_depth} when beginning an |\hbox| + with a paragraph inside. [This refers to a special `paragraph box' + construction, used when an hbox of specified size becomes overfull; + \TeX78 doesn't have the concept of internal vertical mode.] @1083 +D41. Also initialize \\{tail} in that case. @1083 +M42. Also put the result of line-breaking into the correct list. +T43. Fix a typo in the \\{free_node} routine (`\\{link}' not `\\{llink}'); + by strange chance it had been harmless until today. @130 +F44. Fix bug: \\{post_line_break} forgot to set \\{adjust_tail}. @889 +D45. Update \\{act_width} properly when looking for end of word while + line breaking. @866 +B46. Repair the ``tricky'' part of \\{get_node}: I used the \\{info} field + when I meant to say \\{llink}. @127 +# Now the |\corners| macro of |acphdr| works! [See |\setcornerrules| + in {\sl The \TeX book}, page 417.] +D47. Reset \\{contrib_tail} properly in \\{build_page}. @995 +T48. Fix typo (|-| for |+|) in computation of \\{page_total}. @1004 +S49. Change the page-breaking logic: \TeX\ reached \\{fire_up} with + $\\{best_page_break}=\\{null}$ in one case, + since the badness was too bad. @1005 +M50. Perform the operation \\{delete_token_ref}(\\{top_mark}) only when + $\\{top_mark}\ne0$. @1012 +F51. Make \\{scan_toks} omit the initial |{| of an |\output| routine. @473 +I52. Insert a comma to make memory usage statistics look better. @639 +# About seven good hours of debugging today. +# Tomorrow will be first-output day (I hope). +* 14 Mar 1978 +# (Came in evening after sleeping most of day, to get computer at better time.) +# (Some day we will have personal computers and will live more normally.) +# 8:30pm, began to enter corrections to yesterday's problems. +I53. Issue an error message for non-character in filename or in font name. @771 +I54. Display `|...|' for omitted stuff in \\{show_context} routine. @643 +L55. Watch out for the |SAIL| syntax `$\alpha+\beta\mathbin{\rm lsh}\gamma$'; + it doesn't shift $\alpha+\beta$ left (only $\beta$). @464 +# That error was very hard to track down; it created a spurious link field + and sent $\\{hash}[0]=\null$|\beta| to the scanner! +# I could have found this bug an hour sooner if I had looked at the correct + stack entries for \\{name} and \\{token_type}. +D56. Show the correct page number when tracing pages before output is shipped. @638 +F57. Remember to nullify a box after using it. @1079 +I58. Issue an error message if\/ |\box255| isn't consumed by the output routine. @1015 +# I'm having trouble with the |BAIL| debugger; + it makes an illegal memory reference and dies, + when single-stepping past the entry to recursive procedures + \\{hlist_out} and \\{vlist_out}. So I have to reload and be careful + to go thru these procedures at high speed. +P59. Fix bug in comment (memory parameter description said $\ge$ not $\le$). @11 +B60. Fix typo in definition of rule output (said $x,y$ not $\\{x0},\\{y0}$). + [This part of the code went away when |DVI| files were introduced.] +B61. Correct the embarrassing bug in shellsort, where I said `$\le\\{str}[k]$' + not `$\le t$'. + [The first \TeX\ had to sort all output by vertical position on page.] +M62. Make \\{start_input} set up \\{job_name} in the form needed by \\{shipout}; + it uses obsolete conventions. @532,537 +L63. Insert |(| and |)| into the |SAIL| macro definition of \\{new_string}. + [This macro was for pre-|DVI| output.] +M64. Unscramble the parameters of \\{out_rule}: + The declaration was $(\\{x0},\\{y0},\\{x1},\\{y1})$ + while the call was $(\\{x0},\\{x1},\\{y0},\\{y1})$. +# 4:30am, \TeX's first page is successfully output! +# (It was `|\titlepage\setcpage1\corners\eject\end|'.) +* 15 Mar 1978 +# 10:30pm. Today I'm instrumenting the line-breaking routine and putting it + through a bunch of tests. +# (The inserted instrumentation had bugs that won't be mentioned here.) +C65. Don't abort the job when \\{eq_destroy} redefines a + \TeX\ control sequence. @275 +# The first word of a paragraph won't be hyphenated \dots\ so be it! +T66. Fix the typo in \\{line_break} that spoils the test for + `letters in the same font'. @896 +# The effect of that typo was to suppress all hyphenation attempts. +B67\>25. Replace the space at paragraph end by fillglue, not by zero. @816 +L68. Pack the hyphen character properly into its node. @582 +T69. Fix a typo (`{\tentex\char'30}' for `|+|') + in the computation of \\{break_width}. @838 +M70. Change the |\end| maneuver; the present code doesn't end the job, + since I forgot that \\{back_input} uses \\{cur_tok}. @1054 +A71. Add a parameter to \\{try_break}, since the width is different at + a discretionary hyphen. [This problem will be solved differently in \TeX82, + when discretionaries become much more general.] @840 +F72. Bypass kern nodes in pre-hyphenation. @896 +F73. Supply code for the forgotten case `$<$ |"a"|' in pre-hyphenation. + [This case was later generalized to a test of \\{lc_code}.] @897 +B74. Change $\\{mem}[q]$ to $\\{prev_break}(q)$ in the + reverse-linking loop. @878 +# (Such blunders. Am I getting feeble-minded?) +A75. Introduce special logic for \\{eject_penalty}; I was wrong + to think that forced ejection was exactly like an + infinitely negative penalty. @851 +A76. Use $(1+b)^2-p^2$ when computing demerits with $p<0$. @859 +# 6:30am. The line-breaking algorithm appears to be working fine + and efficiently. + On small measures (about 20 characters per line), it gives overfull boxes + instead of spaced out ones. Surprising but satisfactory. +* 16 Mar 1978 +# 9pm. The plan for tonight is to test page breaking and more paragraphing. +G77. Insert `|\topskip|' glue at beginning of page. @1001 +I78. Add `|\pausing|' feature. @363 +M79. Fix discrepancy: In \\{make_accent} I called \\{vpackage} + with a pointer to the first list item, but \\{vpackage} itself assumes + that the parameter is a pointer to that pointer. [The + \\{vpackage} of \TeX82 will be different.] @668 +# I checked for other lapses like that. Result: 14 calls OK, 12 NG. +M80. Create a new temporary list head location, \\{hold_head}, since there's + a case where \\{vpackage} is improperly called with + parameter \\{temp_head}. [At this time \\{vpackage} uses \\{temp_head} + to make a list of all insertions found.] @1014 +# 11:30pm. The machine is tied up again. +F81. Write code to handle charnodes in vlists; I forgot that I'd decided + to allow them. [Later I prohibited them again!] @669 +F82. Combine the page lists before pruning off glue + in \\{fire_up}; otherwise the pruning doesn't go far enough. @1017 +B83\>25. Fix typo where line-breaking starts: `\\{fill_glue}' should be + `\\{new_glue}(\\{fill_glue})'. @816 +I84. Add |/q| to |xspool| command (cosmetic change). [This changes a system + command that causes \TeX\ output to be printed on the Xerox Graphics + Printer (XGP), the progenitor of future laser printers; + the |/q| option says that the queue of printing requests should be + displayed on the user's terminal.] @642 +E85. Don't write a form feed after the last page of output. @642 +# To fix this, I reorganized \\{ship_out}, and it became simpler. +T86. Correct a typo (`{\tentex\char'30}' for `|+|') in the \\{vlist_node} case + within \\{hlist_out}. [The output routines were quite different + at this time, because output went directly to the XGP.] @622 +I87. Change the message `|completed page|' to `|Completed for page|'. @638 +B88\>48. Fix yet another typo in the computation of \\{page_total}: My original + code said $\\{stretch}(p)$ instead of $\\{stretch}(q)$ (terrible). @1004 +P89. Document the dirty trick about \\{bot_mark}'s reference count. + [That trick is, fortunately, no longer useful.] @1016 +A90. Rethink the algorithm for contributing an insertion: The original code + tests for a page break after incrementing the totals but + before the \\{contrib_list} is updated. [\TeX78 handles insertions + in a hardwired manner that will be greatly generalized in \TeX82.] +F91. Fix \\{get_node} again: + After the variable memory overflows, control falls through to \\{found} + instead of going to the \\{overflow} call. @125 +# I spent several hours tracking down that data structure bug! +B92. Change \\{new_line} to \\{next_line} in yet another print command (see \#7). +A93\>75. Amend the line-breaking algorithm: + |\break| in paragraph doesn't work with really bad breaks. @851 +# A problem to be diagnosed tomorrow: Each time I run the test program, + the amount of memory in use grows by 13 cells not returned. +# Seven hours tonight. +* 17 Mar 1978 +G94. Introduce \\{dead_cycles} to keep |\end| active until \\{ship_out} + occurs. @1054 +E95. Don't call \\{line_break} with an empty list. @1096 +S96. Take proper account of the (infinite) fillglue when computing + the width of a paragraph line preceding a display. @1146 +M97. Add a new parameter to \\{hpack} so that \\{line_break} won't be called + at the wrong time. + [This is for the soon-to-be-obsolete feature described in \#40.] +L98. Give a warning message if there's an |\hfill| in the middle of a paragraph; + fillglue upsets the line breaker, + because floating-point calculations don't have sufficient accuracy. @868 +# I spent an hour looking for another bug in \TeX, but the following one was in \MF: + The \\{xgp_height} data in fonts had been supplied wrong. +# It took two hours to recompile 32 fonts with proto-\MF. +R99. Make \\{show_node_list} and \\{show_token_list} + more robust in the presence of software bugs. @182 +D100\>97. Do not remove nodes with \\{eject_penalty}, + when the new parameter to \\{hpack} is \\{true}. +E101\>97. Put a fast exit into \\{hpack}; e.g., at glue nodes, test `{\bf if} + \\{paragraphing} $\land$ $\langle$current width is large$\rangle$'. +# 2am. I have to go to bed ``early'' tonight. +* 18 Mar 1978 +# 3:30pm. (Saturday) +I102. Add a parameter to \\{check_mem} (to suppress display unless needed). @167 +G103. Introduce a user-settable parameter |\maxdepth|, and + pass it as a parameter to \\{vpackage}. @668 +# I realized the need for |\maxdepth| while fixing insertions (see \#90). +G104. Introduce a user-settable parameter for \\{line_break}: The constant + 2.0 in my original algorithm becomes |\jpar| + [later |\tolerance|], to be set like |\tracing|. @828 +D105. Reclaim the \\{eject_penalty} nodes removed during line-breaking. @879 +# (Those were the 13 extra nodes reported on Thursday.) +# The \\{init_align} procedure worked right the first time! +# Also \\{init_row}, \\{init_col}. But then\thinspace\dots +S106. Rethink the command codes: \\{endv} in a token list has too high a + code for the assumptions of \\{get_next}. @207 +A107. Add a \\{prev_cmd} variable for processing delimited macro parameters; + the original algorithm loses track of braces. + [The rules will change slightly in \TeX82, and + \\{rbrace_ptr} will take on a similar function.] @400 +S108. Make the \\{get_next} routine intercept |&| and |\cr| tokens. @342 +# I'd thought I could just put |&| and |\cr| into + \\{big_switch} [i.e., in the stomach of \TeX, not the eyes]; + that was a great big mistake. +R109. Make more error checks on \\{endv}; e.g., it must not occur in + a macro definition or call. @780 +S110\>108. No, rethink alignments again; the new program still fails! @768 +# For the first time I can glimpse the + hairiness of alignment in general (e.g., `|\halign{\u#\v&...|' + when |\u| and |\v| are defined to include |&|'s and possible + alignments themselves). +# I think there's a ``simple'' solution, by considering only whether + an alignment is currently active [in \S342]. +# 11:30pm. Went to bed. +* 19 Mar 1978 +# Woke up with ``better'' idea on how to handle |&| and |\cr|. +# (Namely, to consider a special kind of\/ |\def| whose parameters don't interrupt + on |&|'s and |\cr|'s.) +# But replaced this by a much better idea (to introduce \\{align_state}). +# 11pm. Began to use computer. Performed major surgery + (inserting \\{align_state} and updating the associated routines + and documentation). +D111. Pop the alignment stacks in \\{fin_align}. @800 +T112\>110. Fix a (newly inserted) typo in \\{show_context}. @314 +D113\>110. Set \\{align_state} false when a live |&| or |\cr| is found. + [Originally \\{align_state} was of type \\{boolean}.] @789 +I114. Insert |\cr| when `|}|' occurs prematurely in an alignment. @1132 +M115. Remember to record \\{glue_stretch} when packaging an unset node. @796 +# I had a mistake in |acphdr| definition of\/ |\quoteformat|; also extra spaces. +# My first test programs, used before today, were contrived to test macro + expansion, line-breaking, and page layout. +# Next I'm using a test program based on Volume 2. +C116. Make carriage-return, space, and tab equivalent for macro matching. @348 +F117. Omit the reference count node when displaying a mark. @176 +B118. Correct a silly slip: I wrote `\\{type_displacement}' instead of + `\\{value_displacement}' when packing data in a penalty node. @158 +M119. Don't go to \\{build_page} after seeing |\noindent|; \TeX\ isn't + ready for that. + [In the original program, this was an instance of a bad {\bf goto}.] @1091 +# I had undesired spaces coming thru the scanner in my macro definitions + of\/ |\tenpoint| [see {\sl The \TeX book}, page 414]. +# 4am. \TeX\ now knows enough to typeset page 1 of Volume 2! +# Also it did its first ``math formula'' (namely `|$X$|') without crucial error. +# (Except that the italic correction was missing for some reason.) +D120. Remember to decrement \\{cur_level} in \\{fin_align}. [The routines will + eventually become more general and use \\{unsave} here.] @800 +D121. Remember to increment \\{cur_level} in error corrections by + \\{handle_right_brace}. [A better procedure will be adopted later.] @1069 +T122. Fix a typo: (`|{|' instead of `|}|') in error message for $\\{mmode}+ + \\{math_shift}$. @1065 +R123\>99. Make \\{show_noad_list} more robust and more like the new + \\{show_node_list}. [The routines will be combined in \TeX82.] @690 +L124. Fix a typo in \\{char_box}: should say \\{font_info_real}. + [In \TeX78 a single array + is used for both \\{real} and \\{integer}; in \TeX82 things will be + \\{scaled}.] @554 +B125. Fix typos in the definitions of \\{default_rule_thickness} and + \\{big_op_spacing}; they shouldn't start at \\{mathex}(7). @701 +B126. Reverse the \\{before} and \\{after} conventions in math nodes. @1196 +# I had them backwards; this turned + hyphenation on just before math, and off just after it! +# Seven and a half hours debugging today. + Got through the test program a little more. + But \TeX\ blew up on `|$Y+1$|'; tomorrow I hope to find out why. +* 20 Mar 1978 +# 8pm. I decided to work next on a super-hairy formula. +C127. Change `|\ascii|' to `|\cc|' (character code). [This name will change again + later, to `|\char|'.] @265 +E128. Don't bother to store a penalty node at the beginning of |$$| when + the paragraph-so-far fits on a single line, since such a penalty + has already been stored. [These conventions will change later, and + the |\predisplaypenalty| will always be stored.] @1203 +S129. Avoid reference to \\{tail} in \\{build_page}, + if $\\{nest_ptr}>0$. @995 +B130. Correct a silly + slip in \\{math_comp} (the exact opposite of what I did in \#118). @1158 +B131. Rectify my mental lapse in \\{make_fraction}; I said \\{nucleus} instead of + \\{thickness}. @743 +F132. Mask off the math class when scanning delimiters. @1160 +C133. Allow an optional space after |\def{...}|. [This decision + will be retracted later.] @473 +# My test example is so complicated it causes the semantic stacks to overflow! +L134. Don't test for no pages output by looking at the channel status. @642 +T135. Fix typo in definition of\/ |\mathop| (\\{open_noad} not \\{op_noad}). @1156 +A136. Rewrite \\{fin_mlist}, because `|\left(...\above...\right)|' doesn't + parse correctly; the |\left| goes into the numerator, + the |\right| into the denominator. @1184 +B137. Correct the use of \\{depth_threshold} in \\{print_subsidiary_data}: + Simple fields get shown while others look empty. @692 +I138\>78. Return the carriage before showing the first line of a new file + when pausing. @538 +M139. Fix bug: The call \\{show_noad_list}(\\{mem}[|..|]) should be + \\{show_noad_list}(|..|), in the \\{incompleat_noad} case + of \\{show_activities}. @219 +# 3am. The whole messy formula has been parsed correctly into a tree. +# The easy part is done, now comes the harder part. +F140. Don't shift single characters down in \\{make_op}. @749 +D141. Make \\{clean_box} return a box (as its name implies), not an hlist. @720 +# Font info still isn't quite right, it has the wrong value of \\{quad}. +A142. Retain the italic correction when doing \\{rebox}; + can make $\\{glue_set}\ne0$ a flag for this. [A better + solution will be adopted later.] @715 +B143. Fix the bug that makes \\{rebox} bomb out: $\\{value}(p)$ should be + $\\{value}(\\{mem}[p])$. @715 +# 6am; ten hours today. \TeX\ didn't do |$\pi\over2$| correctly, but was close. +# I found that the \\{rebox} problem (\#142) went away when I fixed the + \\{clean_box} problem (\#141); but I + will leave the extra stuff about $\\{glue_set} \ne 0$ + in the program anyway, just for weird cases. +E144. Omit extra levels of boxing when possible in \\{clean_box}. @721 +# (To do this, I need to face the \\{rebox} problem anyway.) +* 21 Mar 1978 +# 10pm. The computer is rather heavily loaded tonight. +F145. Don't forget \\{thickness} when making a square-root sign (see \#131). + [The rule thickness will later be derived from the character height.] @737 +L146. Define $p$ local to the \\{make_fraction} routine. @743 +# Unwittingly using the global $p$ was a disaster. +I147. Don't show the amount of \\{glue_set} when it's zero. @186 +D148\>142. Make \\{glue_set} nonzero in the result of \\{var_delimiter}. @706 +F149. Fix bug: The \\{math_glue} function didn't return any result. @716 +T150. Fix typo in \\{char_box} ($c$ not $w$); this caused a subscripted~$P$ to come + out the same width as an unsubscripted~$P$. [Later changes in the rules + will move this computation to \S755.] @709 +P151\>144. Revise \\{clean_box} to do operations that are needed + often because of the \\{rebox} change. @720 +D152. Use the new \\{clean_box} to avoid a bug in |\sqrt{\raise...}|. @737 +Q153. Change the definition of\/ |\not| so that it's a relation + (which will butt against the following relation). [All math + symbols and Greek letters are defined in |INITEX| at this + time, not in a changeable format definition.] +I154. Give error message `{\tt Large delimiter must be + in mathex font}', instead of calling \\{confusion}, + since the error can occur. + [This particular error is impossible in \TeX82.] @706 +F155. Change the use of $p$ in \\{var_delimiter}; it isn't always set when I say + {\bf goto} \\{found}. @706 +# Another font problem now surfaced: The mathex meta-font didn't compute \TeX\ info + in a machine-independent way. + (It took two hours to correct this.) +D156. Don't forget to set $\\{type}(b)$ in all relevant cases of + \\{var_delimiter}. @708 +B157. Use the correct sign convention for \\{shift_amount} in \\{hpackage}. @653 +F158. Always kern by \\{delta} when there's no superscript. @755 +M159. Declare \\{space_table} to be $[0\,.\,.\,6,0\,.\,.\,6]$ + not $[0\,.\,.\,7,0\,.\,.\,7]$; otherwise its entries are + pre\-loaded into the wrong positions. [The \\{space_table} in \TeX78 is + $7\times7$; it will become $8\times8$ in \TeX82, + represented as a string called \\{math_spacing}.] @764 +C160. Use a negative value, not zero, to represent a null delimiter. + [Actually zero will come back again later.] @685 +C161\>127. Change |\cc| to |\char|. @265 +L162. Don't use tricky subtraction on packed data when changing $q$ to + an \\{ord_noad} in \\{mlist_to_hlist}; subtraction isn't always safe. @729 +B163. Fix two typos in the \\{space_table} (|*| for |0|). @764 +F164. Initialize \\{cur_size} everywhere (I forgot it in two places). @703 +A165. Reset \\{op_noad} before resetting \\{bin_noad}. @728 +F166. Treat $\\{display_style}+\\{cramped}$ the same as \\{display_style} + inside \\{make_op}. @749 +B167. Shift the character correctly in the non-|\displaystyle| case of + \\{make_op}. @749 +# Still another font problem: The italic corrections are wrong because + the corresponding array was declared \\{real} in proto-\MF\ (and + italic corrections were used in nonstandard way in |mathex|). +B168. Use \\{depth} instead of \\{height} in \\{var_delimiter}. + [Later, both were used.] @714 +Q169. Skew the accents according to the font \\{slant}. [Soon retracted.] @741 +# At this point I think nearly all the math routines have been exercised. +# Tomorrow they should work! +# Eight hours debugging today. +* 22 Mar 1978 +# (Wednesday, but actually Thursday: + I began at midnight because I was proofreading a paper.) +# I checked out the font access tables, slowly (i.e., all the |\mathcode| + and special-character name entries were catalogued). +Q170\>169. Do {\bf not\/} consider slants after all in the math accent + routine, since slanted math letters are put differently into fonts. @741 +B171. Don't use $q$ for two different things simultaneously + in \\{make_math_accent}. @738 +F172. Fix bug in \\{compact_list} (I forgot to advance the loop variable). + [This procedure became unnecessary in \TeX82.] +M173. Avoid conflict between \\{var_delimiter} and \\{mlist_to_hlist}, which + want to use \\{temp_head} simultaneously. @713 +T174. Fix bad typo in \\{overbar} routine ($b$ for $p$). @705 +# Finally \TeX\ got to \\{after_math} after dealing with that + hairy formula\thinspace\dots +T175. Fix another bad typo: $p$ for $b$ this time. @1199 +L176. Insert more parentheses (twice) because of `|lsh|' precedence + in |SAIL|. @1199 +M177\>36. Use the new hanging-indentation conventions when formatting displayed + equations. @1199 +Q178. Recompute penalties so that break is allowed after \\{punct_noad}s. @761 +F179. Center the large delimiters vertically. @749 +Q180. Round all rule sizes (up) before drawing them. @589 +Q181. Provide more space over $x$ in $\sqrt x$, and more space atop vincula. + @705,737 +Q182. Make large delimiters large enough to cover formula height + (important for subscripts, superscripts). @762 +I183. Insert |/ntn=33| on XGP prompt message so that complex math + won't blow the device driver. [See \#84.] +P184\>161. Update the comment about the meaning of\/ |\char|, since it + can be used in math mode. @208 +# Six hours today. +* 23 Mar 1978 +# 11pm, Maundy Thursday. +C185\>104. Make |\tracing| and |\jpar| follow block structure. @283 +# It took me two hours to enter yesterday's corrections, + because the changes were so numerous. +M186. Fix bad call on \\{begin_token_list} when marks are to be scanned. @396 +# Now the formula looks like it should, modulo problems in fonts. +Q187. Prevent an exponent from going below baseline + xheight/4. @758 +B188. Change \\{quad} to \\{math_quad} when finishing a display + (several places). @1199 +A189. Don't use \\{append_to_vlist} when putting an |\eqno| box on a separate + line, because the page shouldn't break at glue there. + [Later, the \\{append} will be used but preceded by an + infinite penalty.] @1205 +S190. Increase the input \\{stack_size}; \TeX\ may need to back up a lot. @11 +A191. Don't assume that $p$ always points to a glue node when + a page is broken. @1017 +A192. Use \\{epsilon} in \\{scan_spec} (I had used a different + small constant). [This was a kludge to avoid the extra + parameter later called \\{exactly} or \\{additional}.] @645 +R193. Introduce a new procedure \\{scan_positive_length}, to prevent + negative or zero lengths in \\{scan_rule_spec}. + [This restrictive rule will be ``overruled'' later.] @463 +B194. Fix ridiculous bug in the leaders routine of \\{vlist_out}: + I had the initialization {\sl inside\/} the loop! @635 +L195. Eliminate confusion between the two temp variables named $h$; + one is \\{real} and the other is \\{integer}. @629 +F196. Include forgotten case (\\{leader_node}) in \\{hlist_out}. + [Type \\{leader_node} will be absorbed + into \\{glue_node} in \TeX82.] @622 +F197. Don't forget to compute \\{x0} in variable horizontal rules. @624 +# Seven and a half hours today. +# \TeX\ seems to be ready to tackle my test file based on Volume 2. +S198. Calculate \\{y00} in horizontal rules as an integer number of pixels + from the baseline, so that the baseline doesn't jump. @589 +* 25 Mar 1978 +# 2am Saturday. (Might as well drop Friday.) +D199\>185. Make \\{def_code} consistent with the new |\tracing| conventions. + [Many tracing options are packed into a single + parameter called |\tracing|.] @1233 +R200\>185. Don't allow users to change nonexistent things like |\catcode1000|. @1232 +F201\>110. Reset \\{align_state} at beginning of \\{init_align}. @774 +F202. Don't forget \\{scan_left_brace} after |\noalign|. @785 +F203\>110. Set $\\{cur_cs}\gets 0$ in \\{get_next}, after |\cr| + causes a switch to the $\langle v_j\rangle$ template. @342 +# Ouch, that was a big bad bug, which took me three hours to find + (since I thought \TeX's low-level scanning mechanism was working). +# Note to myself: I\/ {\bf knew\/} it would be cleaner to define \\{get_next} + so that it sets \\{cur_cs} to zero every time it begins [i.e., + in \S341, where this change will in fact be made in \TeX82]. + But I had avoided this on grounds of efficiency in the inner loop. + Well, now I have earned this tiny bit of efficiency. +D204. Prohibit the first word of an unavailable node from becoming negative. + [The storage allocator of \TeX78 uses + a negative value to signify a node that is available, just as + `$\\{link}=\\{max_halfword}$' will signal availability in \TeX82.] @124 +# That was another bad one, it's not my night. +# At least I'm developing more subtle diagnostic techniques. +M205. Remember to un-negate the top \\{save_stack} entry + when \\{handle_right_brace} finishes an \\{insert_group}. + [This routine was completely revised in \TeX82.] @1100 +F206\>185. Initialize |\jpar| [i.e., |\tolerance|]. @240 +B207. Correct the display of insertion nodes by \\{show_node_list}. @188 +R208. Prevent \\{show_token_list} from generating really long strings + when in a loop. @292 +D209. Increase the reference count of \\{bot_mark} when + \\{vpackage} finds it. [This was later the job of \\{fire_up}.] @1016 +M210. Remember that the tokenlist for a mark ends with a |}|. @1101 +D211. Don't let \\{vpackage} lose the top insert. (It fails when + the very first item is a |\topinsert|.) @1014 +A212. And when that stupid code is corrected, make it handle + insertions first-in-first-out. @1018 +# Seven hours today. +* 26 Mar 1978 +# Easter Sunday, will work till sunrise. +I213. Add an `|i|' feature to the \\{error} recovery routine. @87 +I214. Include a prompt. @87 +C215. Ignore space after |\noalign{...}|. @1133 +# Otherwise, things are going well tonight; + I'm finding more bugs in my test program than in \TeX. +# The `|i|' feature is proving to be very helpful. +# I increased the size of \\{mem} + (now $\\{lo_mem_max}=3500$, $\\{mem_max}=10000$). +# In fact I just needed to increase it again + (now $\\{lo_mem_max}=4500$, $\\{mem_max}=11000$). +R216. Make |INITEX| output \\{mem_top} for consistency checking. @1307 +A217. Calculate the size of delimiters by considering the enclosed formula's + distance from the axis, not from the baseline. @762 +# I'm having trouble with a |SAIL| compiler bug; I must rearrange the program, + more or less at random, until it + compiles correctly. I hope the bug isn't more severe than it appears. +D218\>210. Don't put a new group on \\{save_stack} if a null mark is expanded. + [\TeX82 will remove the `|}|' from the mark text.] @386 +# I had to redo the typewriter-style font since its width tables were wrong. +# And I increased low-memory size again to 5500, then 6500. +# Finally the entire test program was \TeX ed. Happy Easter! Six hours today. +* 27 Mar 1978 +# Beginning at 2:30am. +A219. Move |\vcenter| processing to the first pass of \\{mlist_to_hlist}; + otherwise the height, depth, subscripts, etc., are way off. @733 +C220. Omit space after closing |$$|. @1200 +# Spacing is wrong in the formula $Y_1+\cdots+Y_k$; I have to rethink the use + of three dots. +G221. Make conditional thin space available to user as |\|{\tentex\char'34}. + [Later will retract this.] @226 +Q222. Introduce |\dispaskip| and |\dispbskip| [later called + |\abovedisplayshortskip| and |\belowdisplayshortskip|]. @226 +# Reminder: I need to test line-breaking with embedded math formulas. +I223. Make sure that $\\{interaction}\ne\\{error_stop_mode}$ + in the `|Whoa|' error [\\{fatal_error}]. @93 +B224. Fix a big mistake in the \\{style_node} routine (which points to a glue spec, + not to glue itself); somehow this didn't cause trouble yesterday. + [In \TeX78, style nodes double as placeholders for math glue + like thin spaces.] @732 +C225. Make |\fntfam| obey group structure. [\TeX78's |\fntfam| operation + is a combination of \TeX82's + |\textfont|, |\scriptfont|, and |\scriptscriptfont|.] @1234 +# At this point the test routine for Volume 2 works perfectly. +# But I will change the page width in order to check harder cases. +Q226\>178. Disable automatic line breaks after punctuation in math + (e.g., consider $f(x,y)$). @761 +S227. Represent italic corrections as boxes, not glue, so that they won't be broken. + [The |\kern| command doesn't exist yet.] @1113 +# Eight hours today. +B228. Fix a bug that just clobbered the memory: Call \\{free_avail}, not + \\{free_node}, in the \\{ins_node} case of \\{vpackage}. + [This logic will change completely in \TeX82.] @1019 +* 29 Mar 1978 +# (Wednesday) Again beginning at 2:30am. +Q229. Put still more space above and below fraction lines in displayed + formulas. @746 +G230\>189. Install an infinite penalty feature, which positively suppresses breaks; + use it in displayed formulas whose |\eqno| doesn't fit. @1205 +F231. Call \\{build_page} after finishing a display; and don't + go to the |\noindent| routine because of the next remark. @1200 +S232. Put |\parskip| glue just before a paragraph, not just after + (since it interferes with a penalty after). @1091 +# Although the test program gives correct output, it generates 46 locations + of variable-size memory and 280 of one-word memory that are not freed. +F233. Recycle the ulists and vlists in \\{fin_align}. @801 +M234\>25. Fix bug when deleting space at end of paragraph: + \\{delete_glue_ref}(\\{cur_node}) not + \\{delete_glue_ref}(\\{value}(\\{cur_node})). @816 +# There's also a more mysterious type of uncollected garbage, + a \\{fraction_noad} corresponding to + |$p\choose$|, an \\{incompleat_noad} not completed. +# Couldn't find that one, so I recompiled with \#233 and \#234 corrected. +# Now it gains just 10 locations of variable-size memory and 7 of the other kind. +I235. Extend \\{search_mem} to search \\{eqtb} also. @255 +D236\>143. Fix bug in \\{rebox} when $\\{list_ptr}(b)=0$. @715 +# The seven one-word nodes were generated by this bug; + \\{rebox}\kern-1pt\ put them onto a linked list starting with + $\\{mem}[0]$, growing at the far end! +D237. Remember to complete each \\{incompleat_noad}. @1184 +# This solved the other mystery. I had never noticed that my test output + was actually wrong: |$p\choose k$| came out as `$k$'. +# After these corrections, the test routine worked\thinspace\dots\ I feel + that \TeX\ is now pretty well debugged + (except perhaps for error recovery)---it's time to celebrate! +* 1 Apr 1978 +I238. Don't quit after file lookup fails. @530 +* 2 Apr 1978 +P239. Add \\{\TeX_font_area}, so that it's easier to change the + default library area associated with a device. @514 +* 3 Apr 1978 +L240. Insert parentheses again, to cope with the precedence of\/ |lsh| + when packing data. (See \#55 and \#176.) @1114 +# I had never tried $\\{hmode}+\\{discretionary}$ before! +M241. Remember that \\{back_error} requires \\{cur_tok} to be set. + (Problem can arise during error recovery on parameter |#|$n$ + with $n$ out of range.) @476 +* 4 Apr 1978 +I242. Add a deletion feature to the \\{error} routine. @88 +* 5 Apr 1978 +Q243. Reset \\{space_factor} after |\/| [this was later rescinded] + and after math in text. @1196 +* 10 Apr 1978 +G244\>104. Replace |\jpar| and |\tracing| by a new primitive |\chpar| for parameters. + It allows a user to change those quantities as well as the penalties for + hyphens, relations, binary ops, widows. @209 +* 14 May 1978 +# Beginning to typeset a real book (Volume 2, second edition), not just a test. +Q245. Make math in text end with spacing as if it were + followed by punctuation. [This rule will soon be rescinded.] @760 +F246. Insert |\times| into the hash table; I left it out by mistake. + [It will eventually move into |plain.tex|.] +C247. Change the names of Scandinavian accents from |\o|, |\oslash|, + |\Oslash| to |\a|, |\o|, |\O|. [This will also move to |plain|.] +* 17 May 1978 +B248. Fix a silly bug that hasn't been tweaked until today: + `|\halign to size|' [obsolete in \TeX82] used \\{vsize} + instead of \\{hsize}. @645 +* 19 May 1978 +G249. Add a |\topbaseline| feature [later called |\topskip|]. @1001 +Q250\>245. Subtract the math spacing change of May 14. @760 +A251. Skip past blanks in the \\{scan_math} procedure. [This blank-skipping + will eventually go into \\{scan_left_brace}.] @403 +I252. Introduce a \\{missing_brace} routine [later generalized] to improve + error recovery in $\\{mmode}+\\{math_shift}$, when the top + of \\{save_stack} isn't a \\{math_shift_group}. @1065 +Q253. Adjust the math spacing between closing parentheses and + Ord, Op, Open, Punct. @764 +Q254. Make the underline go further under. @735 +S255\>96. Compute the proper natural width when a displayed equation follows + a paragraph whose fillglue has been deleted by \\{line_break}. @1146 +* 20 May 1978 +A256. Fix the spurious value of \\{prev_depth} inside alignments. @775 +S257. Consider (and defeat) the following scenario: + The u and v lists are built in \\{init_align} using \\{temp_head}; + then while scanning `|\tabskip 2pt\rt{...}|' the macro |\rt| is expanded, + clobbering \\{temp_head}. @779 +# That bug was more subtle than usual. +Q258. Add the parameter \\{num3}, so that the positioning of\/ |\atop| + can be different from that for fractions. @700 +Q259. Add new parameters \\{delim1} and \\{delim2}, so that + |\comb| can use fixed size delimiters, not computed as with |\left|. @748 +* 22 May 1978 +C260\>221. Change |\|{\tentex\char'34} to |\|{\tentex\char'35} and introduce + |\|{\tentex\char'34} as the negative of\/ |\|{\tentex\char'35}. + [Later obsolete.] @226 +L261. Fix the display of negative penalty nodes; \\{show_node_list} is confused + when a negative value has been packed into the middle of a word. @194 +# Memory overflow just occurred with $\\{lo_mem_max}=7500$ and $\\{mem_max}=16384$. + So I have to go to 15-bit pointers. (A problem on 32-bit machines?) +* 23 May 1978 +Q262. Add a new parameter \\{big_op_spacing5}, for + extra space above and below limits of big displayed operators. @751 +F263. Initialize \\{incompleat_noad} in |$$\halign{...}$$|. @775 +# That was another heretofore-untested operation. How much of the code + has not yet been exercised? +F264\>238. Close the file when doing lookup-failure recovery. @27 +I265. Improve the error recovery for `|Extra &|'. @792 +R266. The top piece must be calculated mod 128 in \\{var_delimiter}, + to guarantee a valid subscript range. [Obsolete in \TeX82.] @546 +B267\>252. Fix a blunder in new \\{missing_brace} code. @1065 +B268\>262. Fix a blunder in new code for limits on display operators. @751 +* 26 May 1978 +Q269. Don't insert a new penalty after an explicit penalty in math mode. @767 +# The hash table overflowed; I ought to make it much bigger. +R270\>110. Avoid possible bad memory references in alignment + when there is erroneous input after |\cr|. [Instead of + \\{extra_info}, the value of \\{cur_align} in \TeX78 is negated, + because we need only distinguish |\cr| from |&|.] @789 +S271. Make the dimension parameters like |\hsize| all global, so that they can + be set in the |\output| routine. @279 +# This led to major simplifications, also to major surgery. +# [But it was a kludgy decision, overruled in \TeX82.] +D272\>94. Don't forget to set the type of the new null box in the |\end| routine. @1054 +* 27 May 1978 +# The data overflowed memory again, both low and high, doing Section 3.3.2. +R273\>184. Mask off extra bits of\/ |\char| in math mode, + to avoid bad memory references. @1151 +B274. Zero out the negative |\medmuskip| in script styles. @732 +* 29 May 1978 +S275. Be prepared to handle an undefined control sequence during \\{get_x_token}. + (Can fix this by brute force, using \\{get_token} instead of \\{get_next}.) + @380 +D276. Correct the superscript shift when a single character is raised. @758 +R277\>184. Mask off all but 7 bits in |\char| routine, + to avoid space-factor index out of range. @435 +# More memory capacity overflows. +E278\>22. Fix \TeX's overflow stop so that I don't have to wait for loading of the + |BAIL| debug routines. [System dependent.] @93 +F279. Remember to adjust the page number + when a file page ends in mid-macro. [System dependent.] @306 +* 5 Jun 1978 +R280. Make sure that the arguments of positioning commands don't overflow + their field size. @610 +I281. Report the excess amount when giving an overfull box warning. @666,677 +* 7 Jun 1978 +Q282. Use $\ge$ instead of $>$ as termination criterion in \\{var_delimiter}. @714 +R283. Disallow |\eject| in math mode. [In \TeX78, |\eject| is + distinct from |\break|; in horizontal mode it includes + \TeX82's `|\vadjust{\break}|'.] @1102 +Q284. Don't put too much clearance above |\sqrt| in text style. @737 +* 9 Jun 1978 +G285\>110. Make \\{align_state} an integer variable, not \\{boolean}, + so that |\eqalign| can be within another |\eqalign|. @309 +C286. A |\mark| should expand its input. @1101 +* 10 Jun 1978 +E287. Provide for preloading of fonts. @1320 +L288. Close the output file before switching to edit the input file with + the `|e|' option. @84 +E289. Return adjustments found by \\{hpack} to free storage if + they're not used. [Later, \\{hpack} will detach them only + when they're used.] @655 +Q290. Strive for consistency between \\{make_under} and \\{make_over}. + @735 +* 18 Jun 1978 +B291\>236. Fix a serious error in \\{rebox} + (`$b$' instead of `$\\{list_ptr}(b)$'). @715 +# Strange that such a bug would now surface for the first time! +C292. Remove |\deg| from |INITEX|, since macros suffice. +Q293. Add an extra hyphenation penalty for two hyphenated lines in a row. @859 +* 19 Jun 1978 +S294. Introduce the `\\{no_new_control_sequence}' switch. Among other things, + this will prevent an undefined control sequence following \\{scan_math} + from clobbering the save stack. @259 +* 20 Jun 1978 +L295. Change the badness test + `$\\{glue}\le0.0$' to `$\\{glue}\le0.0001$'. [\TeX82 will avoid such + problems by calculating badness without floating point arithmetic.] @99 +R296. Force \\{badness} to be at most $10^{19}$. @108 +I297. Add \\{end_template} for better error recovery in alignments. @375 +E298\>287. Make |INITEX| more like the real \TeX; my simple scheme for + font preloading was no good because it left thousands of `dead' + words in memory. @8 +E299. Economize disk space by using internal arrays in load + modules that aren't being reinitialized. [System dependent.] +E300. Move the declaration of \\{mem} to the semantics module, so that the + object code will be more efficient. [System dependent. The code of + \TeX78 was divided into separately compiled modules for syntax, + semantics, output, extensions, and general organization.] +* 21 Jun 1978 +# Today I'm working on the user manual. +C301. Disallow |\input| except in vertical mode. [I will change this in + \TeX82, treating |\input| as a case of expansion.] @378 +I302. Add error recovery for \\{endv} and \\{par_end} occurring in math mode. + @1047 +G303. Generalize |\ifT| to |\if T|. @506 +* 22 Jun 1978 +F304. Preload the |\bullet| [later done by |plain.tex|]. +D305\>256. Get the correct \\{prev_depth} at the beginning of an alignment. @775 +C306. Change |\eject| so that it ejects only once. @1000 +* 14 Jul 1978 +I307. Look in standard area if a file isn't found in the user's area. @537 +I308. Echo all online inputs in the transcript file. @71 +* 19 Jul 1978 +Q309. Equalize spacing when only one of numerator/denominator is big. @745 +Q310. Prevent subscript from getting too high above baseline. @757 +R311. Avoid infinite loop when stack overflows: \\{push_input} should say + `{\bf if} $\\{input_ptr}\ge\\{stack_size}\;\land\;\\{interaction}= + \\{error_stop_mode}$'. @321 +* 22 Jul 1978 +C312. Make |\quad| meaningful outside math mode. (All fonts must + be generated again!) @558 +I313. Show the nesting level at the end of \\{show_activities}. + [But I decided not to do this in \TeX82.] @218 +C314. Put in |\>| [namely, |\mskip\medmuskip|; + \TeX78 already has |\|{\tentex\char'35}, for conditional |\thinmuskip|, + as well as the negative amounts |\<|,~|\|{\tentex\char'34}]. + Change the name of vector accent from |\>| to |\b|. [Math spacing + operators will become much more general in \TeX82.] @716 +* 25 Jul 1978 +Q315\>94. Give the correct |\hsize| and |\vsize| to the null boxes created + at |\end|. @1054 +A316\>94. And don't ``append'' them. [Later this was changed, so + that it would work better with generalized output routines.] @1054 +I317\>297. Remove the control sequence |\endv|, + since error recovery is now better. @375 +I318. Define another mode of tracing: It says `|OK|' and stops after + |\showlists|. @1298 +Q319\>244. Give better defaults to parameters. [Later done by |plain.tex|.] @209 +I320. Allow more bits in the packed representation of\/ |\showboxdepth|. @238 +I321. Scan past delimiters and/or dimensions when recovering from + ambiguous fractions. @1183 +R322. Reduce accent numbers modulo 128 or 512, depending on the + mode. @1165 +I323. Include a warning, `|(\end occurred on level ...)|'. @1335 +* 28 Jul 1978 +# (I'm writing Chapter 27 of the manual: `Recovery From Errors'.) +I324. Improve the error message in \\{scan_digit}. [This procedure will change + its name to \\{scan_eight_bit_int}, when the number of registers + increases from 10 to~256.] @433 +I325. Don't report overfull boxes if they're less than .1~point + over. @666,677 +I326. Give the user extra chances to define the font, if \\{read_font_info} + is unsuccessful. @560 +I327. Change default recovery for bad parameter number from |#1| to |##|, since + |#1| won't always work and since |##| is probably intended. @479 +I328. Omit the |"Negative?"| message on things like \\{scan_char_num}. @435 +I329. Improve error recovery when a large delimiter isn't in family~3. + [Obsolete.] +I330. Give a more appropriate error message when the input is `|$\right|'. @1192 +# Currently \TeX\ says `|Missing $|'! +I331. Call \\{back_input} before the error message in \\{back_error}, + not afterwards. @327 +* 1 Aug 1978 +I332. Give an appropriate warning when there's no input file and the user + types `|e|'. @84 +L333. Increase the system pushdownlist size so that the manual will compile. + [Procedures \\{hlist_out} and \\{vlist_out} can recurse deeply.] +# Yesterday I distributed 45 preliminary copies of the manual; today I + took out the ``debugging hooks'' and put \TeX\ up as a system program. +* 2 Aug 1978 +# I'm typing Volume 2 again (currently in Section 4.2.2). Culture shock! +G334. Introduce a |\ragged| parameter, to indicate a degree of raggedness. + [Previously, ragged-right setting was performed when the + |\tolerance|/100 was odd! Eventually a better approach, + with |\rightskip| and such things, will be discovered.] @886 +Q335. Omit the `widow penalty' in one-line paragraphs. @890 +* 5 Aug 1978 +G336. Generalize |\pageno| to |\count|\<digit>. @236 +D337\>285. Update \\{align_state} when recovering from `|Missing {|' and + `|Extra }|' errors. @1069,1127 +I338. Show ``runaway'' tokens, making it easier to pinpoint an error. @306 +* 22 Aug 1978 +G339. Add |\predisplaypenalty|. @1203 +I340. Clarify error messages; they should indicate when something has been + inserted, etc. @1064 +* 23 Aug 1978 +I341\>114. Substitute `|Extra }|' for the losing `|Missing \cr|' error message. @1069 +I342\>213. Go past online insertions in \\{show_context}. @311 +Q343. Exact no penalty for breaking one line before a display. @1145 +I344\>338. Check for runaways at end of file. @362 +I345. Give error message when a macro argument begins with |}|. @395 +* 24 Aug 1978 +L346\>213. Remove extra line-feed in \\{show_context} after printing insertions. + [System dependent.] @318 +* 25 Aug 1978 +Q347. Leave no glue at top of page, even after |\eject|. @997 +* 27 Aug 1978 +P348. Adopt Guy Steele's new version of the \TeX\ source files. [He has + recently made a copy and modified it by introducing + compile-time switches for MIT conventions as an alternative to SUAI. + This is the first time that \TeX\ is being ported to another site; + additional switches for PARC, TENEX, TOPS10, and TOPS20 will be + added later, using the Steele style.] +* 1 Sep 1978 +Q349. Don't pass over leader nodes in the \\{try_break} background + computation. [At this time, leaders have not yet been + unified with glue.] @837 +Q350\>82. Prune away all penalties at the top of a page. @997 +* 4 Sep 1978 +I351\>338. Include `|\|' in error message about a runaway argument. @306 +* 8 Sep 1978 +# I just remade all the fonts, with increased ligature field size. +B352\>350. Insert a necessary {\bf goto} statement in the first branch of + the new penalty routine within \\{build_page}. @997 +* 30 Sep 1978 +M353\>338. Make the token list for runaway arguments meaningful outside + of \\{macro_call}. (I just had a runaway argument ending with + `|\lcm|', which turned out to be the + control sequence in hashtable location 0.) @371 +R354. Avoid infinite loop when recovering from |$$| in + restricted horizontal mode. @1138 +L355. Fix two hyphenation bugs related to |-ages|, |-ers|. + [A completely new algorithm for hyphenation will go into \TeX82.] +Q356. Add |-est| to hyphenation routine; + also disable |puz-zled| and |rat-tled|, etc. +* 4 Oct 1978 +G357. Add new primitive |\vtop|. @1087 +Q358. Treat implicit kerns properly after discretionary hyphens have been + inserted. @914 +* 4 Nov 1978 +Q359. Forget the half quad originally required at left and right when + centering displayed equations without equation numbers. @1202 +* 11 Nov 1978 +R360. Don't let the postamble come out empty. [This could occur if no fonts were + selected.] @642 +* 15 Nov 1978 +C361. Allow optional space after digit in \\{scan_int} routine. @444 +* 17 Nov 1978 +R362. Make the \\{check_mem} procedure slightly more robust. @167 +* 20 Nov 1978 +C363. Make the |\par| in a |\def| match the |\par| that comes automatically with + a blank line. (Suggested by Terry Winograd.) @351 +G364. Add new parameter |\mathsurround| for spacing before and after + math in text. @1196 +G365. Extend |\advance| to allow increase by other than unity. [At this + time it applies only to the ten |\count| registers, and it is + called |\advcount|.] @1238 +* 25 Nov 1978 +G366. Add a new primitive: |\unskip|. @1105 +G367. Add new primitives |\uppercase| and |\lowercase|. @1288 +* 28 Nov 1978 +M368\>338. Don't let |\mark| and \\{macro_call} interfere with each other's + \\{scanner_status}. @306 +M369. Omit extra |}| after \\{show_node_list} shows a |\mark|, + since the right brace is already there. (See \#210.) @176 +G370. Add a new primitive suggested by Terry Winograd: |\xdef|. @1218 +* 29 Nov 1978 +S371. Delete a space following |\else{...}| also in the + false case. [\TeX78 uses braces, not |\fi|, for conditionals.] +D372\>320. Make |\tracing| set |\showboxbreadth| as advertised. @198 +F373. Account properly for kerns in width calculations of \\{line_break}. + @866 +Q374\>364. Delete a \\{math_node} at the beginning of a line. @148 +A375\>339. Guarantee that |\predisplaypenalty=10000| will suppress page breaking + before a display. @1005 +* 6 Dec 1978 +L376. Change the file opening statement to allow lines up to 150 characters long. + [System dependent.] +* 16 Jan 1979 +F377\>365. Initialize \\{negative} properly in the |\advance| routine + with a |\count| as argument. @440 +* 20 Jan 1979 +R378. Try to keep complex, buggy preambles of alignments from + crashing the program. @789 +* 17 Feb 1979 +I379\>376. Give more detailed information when warning about a + long line being broken. [System dependent; + the buffer size in \TeX78 is very limited.] +L380. Declare $p$ local to \\{try_break}, for the ``rare'' case code. + [My original program included the following comment: + ``This case can arise only in weird circumstances due to + changing line lengths, and the code may in fact never be executed.'' + Later Michael Plass will discover that variable line lengths require an + entirely different algorithm, using \\{last_special_line}.] + @847 +F381\>334. Don't omit the raggedness correction when the + last line of paragraph has to shrink. [Obsolete in \TeX82.] +* 22 Feb 1979 +F382\>363. Don't forget to return from \\{get_x_token} after finding |\par|. @351 +Q383. Add a new parameter: |\lineskiplimit|. @679 +C384. Change the syntactic sugar: + `|\hbox par|' replaces `|\hjust to ...{overfull}|'. [This vastly improves on + the old idea (see \#40), but there still is no internal vertical mode.] +C385. Introduce new names |\hbox| and |\vbox| for |\hjust| and |\vjust|. @1071 +G386. Add a new condition: |\ifpos|. [It will later be + generalized to |\ifnum| and |\ifdim|.] @513 +G387. Add |vu| and |\varunit|. [\TeX82 will eventually allow arbitrary + internal dimensions as units of measure.] @453 +G388\>312. Add an |em| unit. @455 +C389. Legalize |\hbox spread |\<negative dimension> [since \\{scan_spec} + no longer uses the sign as a flag]. @645 +* 10 Mar 1979 +C390\>370. Make \\{scan_toks} expand |\count| during |\xdef|. [This will + change later when |\the| and |\number| are introduced.] @367 +* 23 Mar 1979 +Q391. Put only 100000\thinspace pt stretch at the end of a paragraph instead of + 10000000000\thinspace pt. + [In \TeX78, ``infinite'' glue is actually finite but large; in the + language of \TeX82 we would say that |\parfillskip|, which is + not yet user-settable, is being changed to be like |\hfil| instead of + like |\hfill|.] @816 +Q392. Treat the last line of a paragraph more consistently with + the other lines (e.g., when |\hfil| appears in mid-paragraph), by + effectively inserting \\{inf_penalty} at the end. @816 +* 31 Mar 1979 +S393. Ensure that penalty nodes aren't wiped out, in weird cases where + breaks occur at penalties that normally disappear. @879 +* 27 Apr 1979 +A394. Correct the page number count when files begin with an empty page. + [System dependent.] +G395. Allow the \\{math_code} table to be changeable via |\chcode|. + [In \TeX82, |\chcode| will split into |\mathcode| and |\catcode|.] @1232 +I396\>332. Don't accept `|e|' after an error message if not + inputting from a file. @84 +* 29 May 1979 +F397. Don't call \\{end_file_reading} if you haven't already invoked + \\{begin_file_reading}; this could happen when trying to + recover from an error in \\{start_input}.@537 +* 7 Jun 1979 +A398\>306. Be sure to eject two pages, + when |\eject| comes just at the time another break is preferable + (e.g., when the page has just become too full). @1005 +* 27 Jun 1979 +I399\>354. Don't say `|You can't do that in math mode|' when the user + says `|$$|' in restricted horizontal mode! @1138 +* 30 Jun 1979 +G400. Add |wd|, |dp|, |ht| dimension units. @455 +I401\>307. Don't try the system area for file names whose area is explicitly + indicated. @537 +* 1 Jul 1979 +G402. Allow letters as (ASCII) numbers [without the |`| marker introduced + later]. @442 +* 2 Jul 1979 +F403. Fix a |\gdef| bug: If the control sequence was never defined before + [this later became the \\{restore_zero} option], + don't remove it at group end. @282 +* 16 Jul 1979 +I404\>320. Update \\{show_noad_list} to be like \\{show_node_list}. + [The two routines, originally separate, will be merged in \TeX82.] @238 +* 18 Jul 1979 +G405. Extend capacity from 32 fonts to 64 fonts if desired. @134 +Q406. Add new \\{extra_space} parameter to all text fonts (requested + by Frances Yao). @558 +F407. Make each \\{node_noad} print properly in \\{show_noad_list}. @183 +Q408. Make |\jpar| allow any break if it is 1000000 or more. + [In \TeX82, a |\tolerance| of 10000 or more allows any break.] @851 +* 23 Jul 1979 +E409. Introduce new primitives |\hfil|, |\vfil|, |\hfilneg|, |\vfilneg|. @1058 +G410. Add |\ifmmode|. @501 +G411. Add |\firstmark|. @1012,1016 +C412. Allow break at leaders (horizontal mode only). @149 +* 25 Jul 1979 +I413\>213. Revise \\{error} so that online insertions work properly + after end-of-file errors. @336 +B414\>411. Change `{\bf if} $\\{first_mark}\ne0$' to + `{\bf if} $\\{first_mark}\ge0$' [because $-1$ + is used to indicate `not yet given a value']. @1012 +* 28 Jul 1979 +C415\>370. Stop |\xdef| from expanding control sequences after |\def|'s. + [This decision will be rescinded later, after several more years of + experience with macro expansion will suggest better ways to cure + the problem.] @366 +I416. Change symbolic printout for control symbols. [System dependent.] @49 +L417\>308. Avoid linefeeds in the transcript file. [System dependent.] +C418\>370. Expand |\topmark|, etc., in |\xdef|. @366 +* 4 Aug 1979 +B419\>413. Fix an error introduced recently: |\par| was suddenly + omitted at end of page. [System dependent.] +* 11 Aug 1979 +P420. Change error messages that use |SAIL| characters not in + standard ASCII. @360 +* 28 Aug 1979 +D421\>411. Move the command `$\\{first_mark}\gets-1$' from \\{vpackage} + to \\{fire_up}. @1012 +S422\>403. Correct a serious |\gdef| bug: + Control sequences don't obey a last-in-first-out + discipline, so \TeX\ loses things from the hash table when deleting a + control sequence. @259 +# To fix this, I either need to restrict \TeX\ (so that + |\gdef| can be used inside a group only for control sequences already + defined on the outer level) or need to change the hash table algorithm. + Although all applications of \TeX\ known to me will agree to the + former restriction, I've chosen the latter alternative, because it gives me + a chance to improve the language: Control sequences + of arbitrary length will now be recognized. +D423. Make sure that \\{unsave} cannot call \\{eq_destroy} + with a value from the upper part of \\{eqtb}. @282 +# I noticed this long-standing bug while fixing \#422. It had very + low probability of causing damage (e.g., it required a certain field + of a floating-point number to have a certain value), but it would have + been devastating on the day it first showed up! +* 29 Aug 1979 +F424. Call \\{eq_destroy} when a control sequence is |\gdef|'ed + after being |\def|'ed. @283 +F425\>418. Treat the first token consistently + when |\topmark| and its cousins are expanded in \\{scan_toks}. @477 +# Now I've checked things pretty carefully and I think \TeX\ is ``fully debugged.'' +* 25 Jan 1980 +I426\>338. Display runaway alignment preambles. @306 +G427. Introduce active characters (one-stroke control sequences). + [I don't yet go + all the way: The meanings of `|x|' and `|\x|' have to be identical.] @344 +* 7 Feb 1980 +F428\>314. Fix a glaring omission: Op space |\>| was + never implemented in math mode! @716 +* 25 Feb 1980 +G429. Add a new dimension `|ex|' (for units of xheight). @455 +* 3 Mar 1980 +C430\>427. Allow the control sequence |\:| to be redefined + [it was the `select font' operator]; + this allows the character |:| to be active. [Obsolete.] +* 23 Mar 1980 +# An extend-\TeX-for-the-eighties party: +G431. Add a new |\copy| feature. @204 +G432. Add a new |\unbox| feature. @1110 +G433. Add a new |\open| feature [later |\openout|]. @1351 +G434. Add a new |\send| feature [later |\write|]. @1352 +G435. Add a new |\leqno| feature, requested by MDS. @1204 +G436. Add a new |\ifdimen| feature [later |\ifdim|]. @513 +C437. Make |\|\<space> in vertical mode begin a paragraph. @1090 +G438. Add a new |\font| feature [replacing the silly previous convention that + a font must be defined when it is first selected]. @1256 +G439. Add new |\parval| and |\codeval| features [later + |\the|\thinspace\<whatever>\thinspace]. @413 +C440\>427. Don't let active characters gobble the following space. @344 +G441\>208. Add a new parameter to govern amount of token list dumped. [Obsolete.] @295 +G442. Add a new |\linebreak| feature [later replaced by |\break|]. @831 +* 25 Mar 1980 +# (Still working on the above, also thought of more.) +G443. Add a new |\mskip| feature. @716 +G444. Add a new |\newname| feature (soon changed to |\let|). @1221 +G445\>430. Allow any control sequence to be redefined. @275 +I446. Send the output to the user's current file area, even when + input comes from elsewhere. @532 +* 27 Mar 1980 +Q447. Compute the xheight for accents in math mode from + family~1, not family~3. [Obsolete.] +* 28 Mar 1980 +Q448. Increase minimum clearance between subscript and superscript. @759 +* 29 Mar 1980 +Q449\>222. When a display follows a display, the second should have the + `shortskip' glue. @1146 +* 4 Apr 1980 +A450\>445. Look at current token meanings when trying to recognize + |\tabskip| in alignment preambles. @782 +* 23 Apr 1980 +I451. Estimate the length of printed output, for the new + priority feature on our XGP device driver. [System dependent.] +C452\>434. Break long |\send| lines + into pieces so that the file can be read in again. [System dependent.] +* 19 May 1980 +Q453\>182. Don't make |\left| and |\right| delimiters too large; they + need to be only 90\% of the enclosed size. [This eventually + became |\delimiterfactor|.] @762 +* 21 May 1980 +G454. Add a new |\pagebreak| feature [later |\vadjust{\break}|]. @655 +* 13 Jun 1980 +# Today I'm beginning to overhaul the line-breaking routine, + and I'll also install miscellaneous goodies. +G455. Allow a radical sign to be in different font positions. @737 +E456. Clear empty tokenlists off input stacks to allow deeper recursions + (suggested by Jim Boyce's macros for chess positions). @325 +G457. Make |\spaceskip| and |\parfillskip| changeable. @1228 +G458. Add a new parameter |\rfudge| (per request of Zippel) [later |\mag|]. @288 +G459. Add a new parameter |\loose| [later |\looseness|]; + now parameters are allowed to take negative values. @875 +E460. Remove the variable \\{just_par}. [Obsolete; it was the \\{real} equivalent + of an \\{integer}]. +* 14 Jun 1980 +Q461. Install new line-breaking routines, including |\parshape|. + (These major changes are introduced as Michael Plass + and I write our article.) @813 +G462. Add a new parameter |\exhyf| [later |\exhyphenpenalty|]. @869 +* 16 Jun 1980 +S463\>444. Change conventions in \\{eqtb} so that glue is distinguishable + from other equivalents. @275 +A464\>444. Don't expand |\b| in |\xdef{\d\b{...}}| after |\let\d=\def|. + [Obsolete.] +D465\>444. Avoid creating dead storage when doing \\{unsave} in certain regions. @275 +* 17 Jun 1980 +C466. Allow negative dimensions in rules. @138 +* 19 Jun 1980 +B467\>463. Make the new test for glue at the outer level of \\{show_eqtb}. @252 +* 27 Jun 1980 +Q468\>453. Don't let |\left| and |\right| become too small for big matrices. + [This eventually became |\delimitershortfall|.] @762 +* 3 Aug 1980 +Q469. Don't move extra-wide, numbered equations flush left unless + they begin with glue. @1202 +* 15 Sep 1980 +M470\>461. Say `$\ge\\{fz}$' instead of `$>\\{fz}$' in the pre-hyphenation + routine; I'd forgotten my definition of \\{fz} [a variable used to test + for a sequence of lowercase letters in the same font]. @897 +R471\>395. Check the range of the index in |\chcode| before saving the old value. + @1232 +* 18 Sep 1980 +D472\>457. Don't forget to increase the reference count to |\parfillskip|, + or it will mysteriously vanish. @816 +* 19 Sep 1980 +C473\>412. Make leaders break like glue in both horizontal and vertical modes. + @149 +Q474\>364. Make |\mathsurround| break properly at left and right end of lines. + @879 +* 13 Oct 1980 +I475\>461. Remove spurious overfull boxes generated when the looseness criterion + fails. [Obsolete.] +A476\>461. Redesign the iteration for looseness; breakpoints were not chosen + optimally. @875 +E477\>461. Avoid storing a lot of breakpoints when they are dominated by + others. @836 +B478\>366. Don't say `\\{cur_node}' when you mean `\\{mem}[\\{cur_node}]'. @1105 +Q479\>461. Prefer the oldest break to the youngest break + when two break nodes have the same total demerits. @836 +L480\>461. Don't make badness too big for floating-point calculations, + when forced to make an overfull box. [Obsolete.] +* 10 Dec 1980 +R481. Make it impossible to get unmatched `|}|' in a delimited macro + argument. @392 +G482. Add new |\topsep| and |\botsep| features. [These are \TeX78's + way to put space at the edge of inserts, + replaced in \TeX82 by the |\skip| register corresponding + to an |\insert| class.] @1009 +* 6 Jan 1981 +P483. Install new routines for reading the font metrics, using Ramshaw's + |TFM| files instead of\/ |TFX| files. @539 +I484. Abort after reporting 100 errors, if not pausing on errors. @82 +G485. Add new |\spacefactor| and |\specskip| and |\skip| primitives. + [At this time we write `|\specskip3=10pt|' and `|\skip3|' for what + will become `|\skip3=10pt|' and `|\hskip\skip3|' in \TeX82.] @1060 +G486\>366. |\unskip| is now allowed in internal vertical mode. @1105 +* 26 Jan 1981 +B487\>482. Don't say `\\{mem}[$q$]' when you mean `$q$'. (See \#143 and \#478.) @1009 +* 27 Feb 1981 +I488\>417. Put some linefeeds back into the transcript file, in order + to prevent overprinting in listings. [System dependent.] +G489. Add a new |\dpenalty| feature [later |\postdisplaypenalty|]. @1205 +G490. Add the dimension |cc| for European users. @458 +C491. Make \\{scan_keyword} match uppercase letters as alternatives + to lowercase ones (suggested by Barbara Beeton's experiments + with |\uppercase|). @407 +I492. Add nonstop mode so that overnight batch processing is possible. @73 +* 2 Mar 1981 +S493\>422. Fix a still more serious |\gdef| bug: The generality + of\/ |\gdef| almost makes it a crime to + forget {\sl any\/} control sequence names, ever! (The previous bug was + only the tip of an iceberg.) @259 +I494. Issue warning message at the end of a file page if nesting level isn't zero. + [System dependent.] +* 5 Mar 1981 +I495. Keep track of maximum memory usage, for statistical + reporting. [Obsolete.] @125 +Q496\>350. Prune away glue and penalties at top of page after marks, sends, + inserts. @1000 +G497. Allow |\mark| in horizontal mode. [Later it will + be |\vadjust{\mark...}|.] @655 +C498. Allow optional space before a required left brace, e.g., |\if AA {...}|. + [See \#251.] @403 +I499. Issue an incomplete |\if| error, to help catch a bad |\if|. @336 +* 17 Mar 1981 +I500\>494. Omit the warning message at end of a file page unless + the nesting level has changed on that page. [System dependent.] +Q501\>310. Fix the spacing when there is a very tall subscript with + a superscript. @759 +* 20 Mar 1981 +S502\>371. Make space-eating after |\else| fully consistent between the + true and false cases. [Obsolete.] +* 24 Mar 1981 +B503\>496. Change \\{glue_spec_size} to \\{ins_spec_size} + in \\{vpackage} [where insertions are done]. [Obsolete.] +* 5 Apr 1981 +B504\>501. Fix a typo (`|+|' instead of `|-|') in the new subscript code; + this shifted certain subscripts down instead of up. @759 +* 18 Apr 1981 +G505. Make leaders with rules of specified size act like variable rules. + @626,635 +* 29 Apr 1981 +A506\>461. Don't consider $\\{badness}>\\{threshold}$ at a line |\break| + except in an emergency. @854 +* 13 Jul 1981 +C507\>402. Allow other characters as numbers. @442 +R508\>294. Avoid dead storage if a \\{no_new_control_sequence} error occurs. + [Obsolete.] @259 +G509. Add a new |\ifx| feature. @507 +G510. Add new features |\xleaders| and |\cleaders|. @626,635 +* 14 Jul 1981 +S511\>507. Amend the new code for constants; + the `|.|' in `|.5|' is thought to mean \O{056}! @442 +L512\>507. And fix an egregious blunder in that code: New commands at the + end of a procedure are ignored when earlier statements + exit via {\bf return}. @442 +* 4 Aug 1981 +P513. Accept alphabetic codes for all online error recovery options, + instead of insisting on control codes like line feed or form feed. + [The original error-recovery codes were suggested by the + conventions of the |SAIL| compiler.] @84 +G514. Add a new |\thebox| feature [later |\lastbox|]. @1079 +* 7 Aug 1981 +G515. Add |fil|, |fill|, and |filll| as units for glue stretching + or shrinking. @454 +I516. Suppress the overfull box error when shrinkage amount is negative. @664 +* 9 Aug 1981 +Q517. Let unset boxes inherit the size of their parent in alignments. @810 +* 12 Apr 1982 +F518. Make |INITEX| dump out the \\{font_dsize} array needed by + the new |DVI| output module. @1322 +* 1 May 1982 +S519\>151. Fix \\{clean_box} so that \\{mlist_to_hlist} cannot make + $\\{link}(q)=0$ and $\\{type}(q)=\\{glue_node}$. @720 +# [That was the historic final change to \TeX78. All subsequent entries + in this log refer to \TeX82.] +* 15 Jul 1982 +# Finished draft of test program and began debugging about 1430 + [2:30\thinspace pm]. Taking my time. +BX1. Change \\{eqtb}[\\{cur_font}] to \\{eqtb}[\\{cur_font_loc}]. @232 +# Not logging changes to the exposition. +# Compile time is about 2 minutes CPU, times 5 for time-sharing; + add another half minute for linking and loading. +# Hash table and \\{get_next} seem to be working, with no changes needed! +# Time out 1630--1815 for Jill's birthday party. +LX2. Insert {\bf begin} \dots~{\bf end} around \\{dump_int} macro. @1305 +IX3. Print two blank spaces before date in \\{open_log_file}. @536 +AX4. Update $x$ and \\{var_used} outside the {\bf for} loop. @1311 +BX5. Change {\bf if} $=$ to {\bf if} $\ne$ as loop exit condition. @1315,1316 +# The |TRIP| test should preload more fonts. +LX6. Insert {\bf begin} \dots~{\bf end} around statistics output. @1334 +FX7. Must \\{get_x_token} when scanning a number. @445 +IX8. Interactive \\{debug_help} needs to print a newline. @1338 +FX9. Include \\{ignore_spaces} and \\{math_accent} in \\{print_cmd_char} cases. @266 +IX10. Don't call \\{confusion} when \\{print_cmd_char} sees unknown code. @298 +# Compiler bug causes stack overflow. Retiring for the night at 2145. +* 16 Jul 1982 +# Starting at 0700; DRF has fixed the compiler. +RX11. Allow arbitrary integer parameters in diagnostic print routines. @237,699 +TX12. Say \\{cur_tok}, not \\{cur_val}, when you mean \\{cur_tok}. @440 +FX13. Make |\pause| effective also on first line of a file. @538 +FX14. Show context after online deletion. @88 +IX15. Bypass reference count when \\{debug_help} shows a token list. @1339 +BX16. Change `{\bf case} $p$' to `{\bf case} \\{type}($p$)'. @1000 +FX17. Fix timing of \\{print_ln} when scrolling help messages. @90 +PX18. Make \\{other_char} the default category for ASCII control codes too. @232 +AX19. Use special scanning method for font number in \\{new_font}. @1257 +# Eating lunch, 1020--1035, while the machine slowly recompiles everything. +FX20. Don't forget to increase $k$ in the {\bf while} loop. @355 +DX21. Adjust \\{limit} properly after line changed when pausing. @363 +FX22. Remember to return a value in \\{new_spec} and \\{new_penalty}. @151,158 +# Now stepping through \\{line_break} in simple case. +AX23. Don't prune unwanted nodes if $\\{cur_p}=\\{null}$. @877 +FX24. Print a closing parenthesis when displaying glue nodes. @189 +SX25. Use \\{last}, not \\{limit}, in \\{term_input}; else error prompt causes + trouble when $\\{state}=\\{token_list}$. @71,87 +DX26. Set $\\{first}\gets\\{limit}+1$ after \\{init_terminal}. @331 +DX27. Make sure \\{set_trick_count} is always performed. @317 +* 17 Jul 1982 +IX28. Add new diagnostic feature |\tracingcommands|. @299,1031 +# Debugging of system-dependent code not shown in this log. +# Tangling \TeX\ now takes 1.75 minutes; about 75K bytes, 108K tokens. +# Redundant semicolon sends Pascal compiler into infinite loop! +FX29. Initialize $\\{passive}\gets\\{null}$. @864 +AX30. Fix pseudoprinting when the line is empty. @318 +EX31. Merge adjacent free areas of dynamic memory before dumping. @131 +FX32. Print the word |mode| in \\{print_mode}. @211 +IX33. Improve message and help in case of weird error. @415 +GX34. Allow optional space after |\def| and similar constructions. @473 +MX35. Declare \\{alpha} to be integer in \\{read_font_info}. @560 +AX36. Fix timing of \\{back_input} in \\{scan_dimen}. @448 +IX37. Back up after missing number error. @446 +IX38. Show the `|at|' size that is considered improper. @1259 +IX39. Streamline the dialog in \\{debug_help}. @1338 +MX40. Take output of \\{the_toks} from the advertised place. @467,1297 +TX41. Say \\{trie_fix}($q$), not \\{trie_fix}($p$). @959 +SX42. Decrease low limit of \\{error_count} to $-1$. @76 +* 18 Jul 1982 +FX43. Clear initial reference count of macro definitions. @473 +AX44. Fix timing of \\{back_input} in \\{scan_glue}. @461 +BX45. Use \\{cur_val_level}, not \\{cur_val}, when checking levels. @461 +BX46. Multiply |fil| units by $2^{16}$ for correct scaling. @454 +BX47. Don't confuse \\{glue_base} with \\{skip_base}. @1237 +AX48. Fix \\{print_scaled} so that 0.01 doesn't come out |0.1|. @103 +IX49\>X28. Show mode changes when tracing commands. @299 +LX50. Don't say {\bf if} $(n=0)\lor(\,\ldots\;\hbox{\bf div}\;n)$ in Pascal. @105 +BX51. Don't confuse \\{box_flag} with \\{box_code}. @1075 +SX52. Reset \\{offset} on \\{print_ln} even in \\{no_print} mode. @57 +SX53. Fix restarting of interrupts after \\{big_switch}. @1031 +LX54. Don't loop {\bf for} $k\gets a$ {\bf to} $b-1$ when $b=0$ if $k$ is + declared nonnegative. +IX55. Put `|=|' sign into the \\{format_ident}. @1328 +SX56. Allow $r$ to be any integer in \\{get_node}. @125 +IX57. Don't put the output of \\{print_file_name} in quotes. @518 +IX58. Say `|dumped|' after dumping. @1311 +EX59. Eliminate unnecessary initialization code. @1332 +LX60. Get the file reading started right when beginning to undump. @1308 +IX61. Give forlorn message if format file can't be loaded. @1303 +FX62. Assign value to \\{cur_val} after glue arithmetic. @1239,1240 +* 19 Jul 1982 +LX63. Don't say {\bf if} $p>\\{max}\lor\\{free}[p]$ in Pascal. @169 +AX64. Fix memory-undump logic; loops are out of phase with input. @1312 +BX65. Undump \\{hyph_word}[$j$], not \\{hyph_word}[$k$]. @1325 +# At last |trip.fmt| loads without bombing out. +PX66. Remove assignment of array to array, not allowed by IBM Pascal + (Susan Plass). @167 +PX67. Simplify an expression that's too big for IBM Pascal (Susan Plass). @1009 +AX68. Go to \\{contribute}, not \\{done}, after insertions. @1000 +IX69. Decrease \\{depth_threshold} if there's not enough string space. @198 +IX70. Show rules as `{\tt\char`\|}' in short displays. @175 +IX71. Don't show null glue in short displays. @175 +SX72. Set $\\{job_name}\gets0$ as part of output initialization. @528 +SX73. Don't complain of infinite shrinkage on |0pt minus 0fil|. @825,976,1009 +IX74. Use different prompt at beginning when accepting a file name. @37 +FX75. Reset \\{last_glue} on nonglue nodes. @996 +BX76. Remember to call \\{error} after printing |OK|. @1293 +LX77. Insert {\bf begin} \dots{ \bf end} around program text of section. @1025 +FX78. Define the |\shipout| primitive. @1071,1073 +AX79. Introduce \\{write_loc} analogous to \\{par_loc}. @1344,1371 +FX80. Dump and undump \\{par_loc} and \\{write_loc}. @1313,1314 +FX81. Allow \\{the} in \\{scan_the} [later \\{scan_something_internal}]. @413 +EX82. Interchange command codes $\\{the}:=:\\{number}$ [later \\{convert}]. @210 +BX83. Don't confuse \\{breadth} with \\{depth}. @236 +IX84. Add string printing feature to \\{debug_help}. @1339 +FX85. Set $\\{state}\gets\\{mid_line}$ in \\{begin_file_reading}. @328 +# Time out 2105--2200 to pick up Jenny from driving lesson. +LX86. Keep $c\le127$ when deleting 99 tokens. @88 +SX87. Don't check for \\{str_room} error when $\\{selector}=\\{new_string}$. @1328 +* 21 Jul 1982 +IX88. Gather more statistics: String usage, font info, hyphen exceptions, stacks. @1334 +DX89\>X79. Initialize \\{write_loc} from \\{cur_val}, not from \\{cs_ptr}. @1344 +FX90. Remember to pack file name for |\open|. @1374 +SX91\>X34. Defuse |\outer| test before scanning optional space after `|}|'. @473 +SX92. Don't allow \\{prepare_mag} to cause errors after \\{jump_out}. @84 +# The first page of |DVI| output is {\sl perfect\/}! Pause to play piano. +BX93. Don't confuse \\{dimen_base} with \\{scaled_base}. @1237 +DX94. Initialize $\\{link}(\\{page_head})\gets\\{null}$ when beginning a page. @991 +SX95. Correct \\{cur_height} more often, since \\{max_depth} might be negative. @972,973 +AX96. Calculate page dimensions properly after vertical kerns. @973 +SX97. Install new \\{page_contents} logic to handle interaction between + insertions and |\topskip|. @987,1008 +SX98. Allow \\{top_skip} glue to be a valid breakpoint. @1001 +FX99. Don't forget to count \\{dyn_used} in inner loop [erroneous analysis + retracted later]. @1034 +FX100. Set $p\gets q$ after migration step. @655 +FX101. Clear \\{prev_graf} to zero at start of paragraph. @1091 +LX102. Put parens into negated \\{leader_flag} macro. @1078 +# Time out 1720--1920 for John's birthday dinner. +DX103. Scale \\{best_height} when adjusting \\{page_goal}. @1010 +AX104. Simplify logic of split insertions; three states become two. @981,1019,1020 +MX105. Don't omit first character when showing a macro argument. @400 +RX106. Prevent clobberage if macros have too many parameters. @390 +* 22 Jul 1982 +IX107. Tell how many |DVI| bytes were output. @642 +IX108\>X88. Adjust for singular or plural statistics. @1320,1334 +SX109\>X98. Consider \\{page_head} a glue node, to inhibit unwanted break. @988 +DX110. Introduce \\{new_skip_param} to keep reference counts updated. @679,969,1001 +DX111. Record the correct size of new insertion after it's split. @1010 +DX112. Use \\{free_node}, not \\{flush_node_list}, when recycling insertion + nodes. @1022 +SX113. Make online insertions work after \\{get_next} is interrupted. @87,324,343 +BX114. Print newline on interruption stop. @98 +SX115\>X34. Put space before \\{end_write_token}. @1371 +BX116. Don't confuse \\{glue_order} with \\{stretch_order}. @838 +TX117. Set $\\{max_dimen}\gets\hbox{\it'7777777777\/}$, not {\it'777777777}. @421 +MX118. Make |\global\textfont| legal. @1211 +BX119. Fetch |\the\textfont| with \\{equiv}, not \\{fam_font}. @415 +BX120. Call $\\{new_ligature}(f,l,\ldots)$ not $(f,c,\ldots)$. @1035 +RX121. Make \\{show_box} work on random garbage. @174,177 +DX122. Count reference to \\{zero_glue} from \\{cond_math_glue}. @1171 +* 23 Jul 1982 +RX123. Allow $\\{avail}=\\{null}$ when undumping. @1312 +BX124\>X110. Set $\\{width}(\\{glue_ptr}(p))$, not $\\{width}(p)$. @679 +AX125. Put \\{begin_file_reading} inside the \\{start_input} loop. @537 +BX126\>X116. Don't confuse \\{glue_stretch} with \\{stretch_order} [the previous + fix went only half\-way]. @838 +BX127. Negate $x$ when calculating badness of shrinkage. @667,678 +LX128\>X121. Remove dangling {\bf else} that parses wrong. @174 +IX129\>X28. Print newline before |{|, not after |}|, when tracing commands. @299 +IX130. Remove colon from overfull box messages. @663,675 +DX131\>X97. Compute \\{page_goal} properly when the first box arrives after + inserts. @1001 +BX132. Don't confuse \\{page_size} [now \\{page_goal}] with \\{best_size}. @1017 +AX133. Put heldover insertions at front of contribution list. @1023 +SX134\>X88. Output stats before closing |DVI| file, since the latter + decreases \\{font_ptr}. @1333 +TX135. Don't call a |\vbox| an |\hbox|. @674 +TX136. Fix misplaced {\bf end} caused by editing error. @675 +* 24 Jul 1982 +DX137. Don't \\{eq_destroy} any paragraph shape when \\{par_shape} is null. @275 +IX138. Omit blank before |\message| at the beginning of a line. @1280 +AX139\>X104. Don't try to split an insertion when \\{best_node} isn't the + split one. @1021 +LX140. Correct another case of `{\bf if} $x\land y$' misunderstood by Pascal. + @1021 +IX141. Provide diagnostic info about insertions via |\showlists|. @986 +IX142. Add `|inside a group|' to clarify a warning message. @1335 +IX143. Report \\{prev_depth} on a separate line in |\showlists|. @219 +SX144. Back up input to avoid unexpected clobberage of \\{cur_tok}. @1090 +# Wow what a bug: \\{new_graf} calls \\{build_page}, which invokes the + output routine, after which `\/{\bf goto} \\{reswitch}' is a {\sl disaster}. +DX145. Add insertion glue to \\{page_so_far} instead of subtracting it from + the goal. @1009 +IX146. Put extra blank line before overfull box warning. @660 +CX147. Define break at kern consistently between horizontal and vertical lists. @973,1000 +DX148. Renumber so that math nodes are nondiscardable. @147 +TX149. Correct the \\{char_kern} macro: |#|, not $f$. @557 +FX150. Decrease $l$ after reconstituting discretionary break. @916 +EX151. Simplify the hyphen routine, knowing that $\\{link}(s)=\\{null}$. @918 +FX152. Initialize $r\gets q$ in discretionary destruction routine. @883 +* 25 Jul 1982 +AX153. Don't add interline penalty after last line of paragraph. @890 +IX154. Adjust spacing in diagnostic messages. @245 +DX155. Avoid simultaneous use of \\{temp_head} by \\{prune_page_top} and the + page builder. @1017 +FX156. Clear the \\{post_break} field of simple discretionaries. @916 +AX157. Split \\{offset} into independent variables \\{term_offset}, + \\{file_offset}. @54,57,58 +# Am freezing current program as version $-0.25$; a week of TUG lectures + begins tomorrow. +* 5 Aug 1982 +IX158. The `|.err|' file should be `|.log|' instead. @534 +GX159. Allow |\special| strings to contain more than 256 bytes. @585,1368 +MX160\>X99. Undo ``correction'' to a non-bug. @1034 +IX161. Suggest |\&| in help message for unexpected |&|. @1128 +GX162. Make `|E|' a standard option for exiting. @84 +GX163. Restore the use of dead cycles \`a la \TeX78. @1024,1054 +# The previous six changes were suggested during discussions with \TeX82 class. +SX164. Fix global variable conflict between \\{open_log_file} and \\{new_font}. @1257 +CX165. Allow optional `|=|' when assign to font parameter. @1253 +FX166. Set \\{cur_val} after increasing the number of font parameters. @580 +DX167. Set \\{hash_brace} when matching `|{|'. @476 +IX168\>X88. Clarify meaning of statistics printed. @1334 +GX169. Change |DVI| format to include design size. @602,1260 +DX170. Introduce \\{def_ref} for \\{runaway} messages. @306 +MX171. Restore \\{cur_cs} before calling \\{scan_toks}. @1226 +AX172\>X157. Update \\{print_nl} to dual offset conventions. @62 +AX173\>X163. Move endgame logic inside \\{main_control}, because the output + routine becomes active. @1054 +* 6 Aug 1982 +CX174. Allow |INITEX| to load format files. @1337 +EX175. Conserve input stack space by deleting finished token lists. @325 +IX176\>X74. Print the opening `|**|' in the transcript file. @534 +# Now ready to try breaking new ground in |TRIP|. +SX177. Preserve \\{align_state} from tokens deleted online. @88 +DX178. Set $t$ in all branches of \\{scan_toks}. @473 +SX179. Change `$\\{cur_cmd}\le\\{right_brace}$' to `$\\{cur_tok}\le + \\{right_brace_limit}$'; otherwise |\relax| gets through. @477 +CX180. Allow optional |=| when setting |\spacefactor|; disallow zero. @1243 +BX181. Change \\{vpackage}(\\{head}) to \\{vpackage}(\\{link}(\\{head})). @796 +# Shades of 1978! +LX182. Insert missing {\bf begin} \dots{ \bf end}. @798 +* 7 Aug 1982 +LX183. Keep \\{trie_max} declared in non-|INITEX| [later rescinded]. @950 +DX184. Watch out for empty token list when copying. @466 +DX185. Free unused reference count slot when defining |\everypar|. @1226 +GX186\>X163. Introduce |\maxdeadcycles|. @1012 +# I believe the \\{line_break} routine has passed its test perfectly. +SX187. Don't put discretionary after |-| inside a discretionary. @1039 +CX188. Change `|\minus|' to `|\minusthe|' [this feature retracted later]. @413 +BX189. Change \\{cur_p} to $r$ (three places). @875 +AX190. Increase range of \\{hc} to \\{halfword}; otherwise end-of-word mark + might match a vacant entry in the trie. @892 +FX191. Initialize $b$ in \\{shift_case} routine. @1288 +EX192. Don't back up if a space follows a decimal fraction. @452 +BX193. Don't confuse \\{glue_base} with \\{dimen_base}. @1145 +LX194. Guard against anomalous floating-point values in glue display. @186 +* 8 Aug 1982 +SX195. Avoid infinite loop when |\outer| leads to runaways. @339 +# I worked on that problem about two hours before fixing it. +IX196. Move final \\{debug_help} to \\{succumb}, except in batch mode. @93 +RX197. Insert kern after spanned box, to defeat access to floating point. @808 +* 9 Aug 1982 +CX198. Include |\leftskip| and |\rightskip| in displayed equations [rescinded + later]. @1199 +IX199. Trace line-break computations if $\\{tracing_stats}>2$. @846,856 +DX200. Keep \\{prev_p} up to date when passing a string. @867 +# Now stepping through math stuff; a lot is working. +DX201. Set $\\{link}(p)\gets z$ when making a fraction. @747 +CX202. Don't reset space factor when beginning |\valign|. @775 +IX203. Don't show glue setting if $\\{glue_sign}=\\{normal}$. @186 +DX204. Clear \\{glue_stretch} and \\{glue_shrink} when creating an unset box. @801 +BX205. Do \\{vpack} in hmode and vice versa when aligning. @804 +AX206. Remove fallacious call to \\{confusion} after alignment in display. @1206 +AX207. Don't test $\\{mode}=\\{vmode}$ in display, test $\\{nest_ptr}=1$. @1145 +FX208. Show an \\{inner_noad} as well as the other types. @690,696 +DX209. Renumber \\{mu_glue} and \\{cond_math_glue} so that the glue display logic + works. @149 +BX210. Don't confuse \\{cur_size} with \\{cur_style}. @703 +FX211. Advance $p\gets q$ during second pass over mlist. @761 +IX212. Add helpful hint about |\tracingonline=1|. @1293 +TX213. Delete spurious statement left from sloppy editing. @710 +DX214. Change the subtype when \\{mskip} becomes \\{hskip}. @732 +FX215. Don't forget to use the remainder when computing math glue. @716 +IX216\>X199. Improve paragraph diagnostics using \\{short_display}. @857 +IX217\>X199. Introduce \\{artificial_badness} for better diagnostics. @854,856 +* 11 Aug 1982 +AX218. Introduce \\{char_box} subroutine so that \\{var_delimiter} adds italic + correction. @709 +SX219. Save font and char in local variables of \\{make_math_accent}, since + it can be recursive. @738 +FX220. Call \\{error} after decrying an invalid character. @346 +* 12 Aug 1982 +IX221\>X199. Install new format for showing break nodes. @846 +# I have been testing \\{line_break} and I think it's working fine. +BX222. Change $q$ to $p$, in order to catch empty alignments. @812,1206 +SX223. Disallow third part of discretionary in math mode. @1120 +DX224. Don't change \\{tail} if discretionary third part is empty. @1120 +IX225. Say |nonscript|, not |non_script|. @189 +SX226. Inhibit math if |\scriptfont3| is improper. @1195 +IX227\>X199. Introduce {\tt\@}|firstpass| and {\tt\@}|secondpass| comments. @863 +TX228. Change $p$ to $r$ when you mean $r$. @1204 +IX229\>X108. Say |page|, not |pages|, if there's only |1|. @642 +IX230. Insert space before |[]| on truncated |\showlists|. @182 +* 28 Aug 1982 +# Back from vacation after having looked at hardcopy listing of |TRIP| test. +GX231. Allow |dm| as a unit [later |.5dm1| will be |.5\dimen1|]. @455 +IX232\>X108. Singularize |prevgraf 1 lines|. @219 +IX233. Omit trailing zero count registers when showing completed page numbers. @638 +LX234. Avoid clobbering $a$ by introducing a new local variable $t$. @986 +DX235\>X216. Fix diagnostic printing of discretionaries. @858 +IX236. Don't show unset stretch/shrink that's zero. @185 +CX237\>X198. Make |\halign| in displays consistent with other displays. (Namely, + ignore |\leftskip| and |\rightskip| in nonaligned displays; + respect the paragraph shape in aligned displays.) @800,1199 +IX238. Parenthesize `|If you're confused ...|'. @403 +IX239. Say `|\fraction|', not `|\xabovex|'. @697 +FX240. Remember to {\bf return} when you should. @1153 +PX241. Use absolute value to make sure {\bf div} is unambiguous. @737 +BX242\>X218. Don't confuse depth with height. @709 +BX243. Use $\\{delta}-\\{height}$, not $\\{height}-\\{delta}$. @736 +BX244. Increase \\{shift_down} to increase the clearance. @745 +IX245. Don't back up after improper use of |\the|. @428 +IX246. Don't give |0pt| as the default result when looking for \\{tok_val}. @428 +FX247. Initialize \\{second_indent} in the easy case. @848 +FX248. Package the equation number. @1204 +QX249. Don't resort to $v\gets\\{max_dimen}$ when glue doesn't stretch or + shrink. @1148 +IX250. Insert newline before showing current |\botmark|. +FX251. Call \\{error} after giving error message. @784 +AX252. Change implementation of |\number|; it should \\{scan_int}, not + something internal. @471 +PX253. Introduce symbolic constants like \\{format_area_length}. @524 +PX254. Change \\{quit} to \\{jump_out}, since some compilers treat \\{quit} + as a reserved word. @81 +LX255. Add more parentheses to get proper parsing. @1260 +IX256. Say |please| in order to be friendly (or at least polite). @360 +BX257. Don't confuse \\{cur_vcmd} with \\{cur_chr}. @508 +IX258. Use |&| instead of |!| to specify a preloaded format. @1337 +TX259\>X177. Correct |s3| to |s4|. @88 +GX260. Introduce new primitive |\mathchardef|, to save space and time. @1224 +CX261. Use the |[]| convention for noads as well as nodes. @692 +TX262. Correct spelling in call to \\{primitive}: |\xatopx| should be |\xoverx| + [later renamed, thank goodness]. @1178 +* 30 Aug 1982 +RX263. Don't fetch \\{link}(\\{null}) in malformed list. @175 +SX264. Initialize \\{align_state} at a better time so that \\{align_peek} + doesn't see |&| or |\span|. @785,791 +SX265. Outlaw preamble interfering with $\\{align_state}=0$. @789 +CX266. Add level of grouping to alignment to tabskip locality. @774 +FX267. Check \\{align_state} when scanning $\langle u_j\rangle$. @783 +AX268. Move `\\{unsave}; \\{new_save_level}' from \\{main_control} into + \\{fin_col}. @791,1131 +SX269\>X180. Remember \\{cur_chr} when you're looking for optional `|=|'. @1243 +TX270. Change $q$ to $r$ [in code now obsolete]. @804 +IX271. Disable interrupts during \\{back_error} so that help messages aren't + clobbered. @327 +SX272. Introduce \\{slow_print} for printing control sequences. @60 +IX273. Initialize \\{del_code}(|"."|$)\gets0$ for error recovery. @240 +SX274. Call \\{end_file_reading} before calling \\{check_outer_validity}. @362 +IX275. Don't delete an extra `|}|' when |\par| will help find a runaway. @395 +* 31 Aug 1982 +BX276. Don't confuse \\{thin_muskip} with \\{thin_muskip_code}. @413 +FX277\>X266. Recover from error if new \\{align_group} ends abnormally. @1132 +IX278. Recover from error if |\par| occurs when $\\{align_state}<0$. @1094 +CX279. Make |\hskip\the\thinmuskip| and |\mskip\the\baselineskip| erroneous. @413 +GX280. Add |\muskip| and |\setmuskip| analogs to |skip| and |\setskip|. @413,1228 +EX281. Don't output |pop| right after |push|. @601 +# The |TRIP| test looks right; now to test for wasted memory. +# When memory should be empty I find $\\{dyn_used}=18$, $\\{var_used}=267$. +* 1 Sep 1982 +# Made special |MEMTEX| program, designed to track all memory allocation. +DX282. Delete reference to \\{last_glue} when a page is packaged. @1017 +IX283. Include \\{save_stack} in the \\{search_mem} debugging routine. @285 +CX284. Disallow |\vfill| in restricted horizontal mode. @1095 +# Most of the memory locations I thought were wasted were actually in good use. +# Total 192 hours (approx) debugging time so far since July 15. +* 2 Sep 1982 +# Now looking at all zero counts in profile and extending |TRIP|. +EX285. Simplify the creation of |vtop| boxes. @1087 +CX286. Set $\\{space_factor}\gets1000$ after |\hbox|. @1076 +PX287. Introduce preamble into |DVI| format. @617 +SX288. Give special \\{chr_code} to |\relax|. @265 +IX289. Don't show `|(null)|' when token list is null, just show nothing. @295 +EX290. Delete the procedure \\{write_name_string}, which is never used. +CX291. Rename |\xabovex| to |\abovewithdelims|; do the same for + |\xatopx| and |\xoverx|. @1178 +QX292. Improve \\{clean_box} so that it recognizes cleanliness better. @720 +IX293. Report a |Missing delimiter| more meaningfully. @1161 +RX294. Give \\{endv_token} a \\{chr} code of 128 so that it will end a file name. @289 +RX295. Test present of math fonts {\sl after\/} parsing an mlist, not + before. @1138,1195 +IX296. Omit `|recent contributions|' and/or `|current page|' when they are + empty. @218,986 +IX297. Display what \TeX\ has deleted after improper discretionary list + has arisen. @1121 +IX298. Show what math character was undefined. @723 +IX299. Improve the |Incompatible magnification| error; break it into two lines. @288 +DX300. Put new cases into \\{flush_node_list}, to recycle mlist noads. @698 +* 6 Sep 1982 +FX301\>X300. Insert a necessary `{\bf goto} \\{done}' in that new material. @698 +# It took two hours to diagnose that {\bf goto} problem. +TX302\>X295. Change `|2|' to `|3|' in help message for extension fonts. @1195 +IX303. Add a special note if material is being held over for the next output. @986 +RX304. Divide before multiplying in \\{make_left_right}, to avoid overflow. @762 +IX305. Introduce the \\{box_error} routine. @992 +FX306. Clear \\{arith_error} after overflow has been reported. @460 +BX307\>X249. Don't confuse \\{stretch} with \\{glue_stretch}. @1148 +DX308. Set $\\{glue_sign}\gets\\{normal}$ when packaging with glue ratio + zero. @558,664 +AX309. Test for overflow before attaching the sign. @448 +# That all worked! Now trying |min_quarterword| negative. +LX310. Take absolute value before applying {\bf mod} in \\{new_trie_op}. @944 +LX311. Say $\\{qi}(c)$, not $c$, when testing |TFM| flags [now obsolete]. @573 +LX312. Initialize \\{token_ref_count}(\\{def_ref}) to \\{null}, not zero. @473 +LX313. Change the type of \\{vsplit} parameter $n$ from \\{quarterword} to + \\{eight_bits}. @977 +LX314. Initialize \\{null-delimiter} different form \\{null_character}. @685 +LX315. Insert \\{qi} twice in \\{scan_delimiter}. @1160 +FX316. Insert \\{qi} in \\{scan_math}. @1151 +FX317. Insert \\{qo} in \\{fetch}. @722,723 +FX318. Insert \\{qi} in \\{set_math_char}. @1155 +FX319. Insert \\{qi} in \\{math_ac}. @1165 +FX320. Insert \\{qo} in \\{mlist_to_hlist}. @755 +IX321. Use brackets around 8-bit characters in \\{print_ASCII}. @68 +IX322. Include \\{hyph_list} in the \\{search_mem} debugging routine. @933 +# Now compiling non-|INITEX| to try an industrial-strength version. +LX323. Add {\bf return} to \\{final_cleanup}, because some Pascal compilers + insist that each label be used. @1335 +DX324. Compute \\{par_token} when undumping. @1314 +* 11 Sep 1982 +IX325. Emit newline before file name, if near end of line. @537 +CX326. Define |\ifx| for arbitrary tokens. @507 +* 12 Sep 1982 +IX327. Don't ask users to type |x| twice before exiting. @84 +GX328. Install new features |\openin|, |\read|, |\ifeof|, |\closein|; rename + existing |\open|, |\send|, |\close| to be |\openout|, |\write|, + |\closeout|. @209,313,1275 +GX329. Install new feature |\expandafter|. @368 +PX330. Change the default file area from `|<TeX>|' to `|TeXinputs:|'. @574 +* 13 Sep 1982 +GX331. Install new feature |\string|. @472 +AX332. Remove spurious space printed by \\{sprint_cs}. @263 +# All tests passed now! But when I played with the system I found another bug + (undetected by |TRIP|): +FX333. Set $r\gets s$ after matching macro parameter tokens. @397 +* 16 Sep 1982 +IX334\>X199. Introduce serial numbers in line-break records, improving + readability and independence. @846 +IX335. Don't abort when \\{file_name_size} is exceeded. @519 +* 17 Sep 1982 +IX336. Remove unwanted period from font capacity message. @567 +* 18 Sep 1982 +GX337\>X329. Make |\expandafter| more powerful by moving it from semantics + to syntax [i.e., from stomach to mouth]. @368 +* 19 Sep 1982 +IX338. Improve error recovery for `|Missing number|'. @415 +* 22 Sep 1982 +QX339. Suppress italic correction between letters in math mode except in math + fonts. @752 +* 24 Sep 1982 +PX340. Define $\\{null}=\\{mem_bot}$, not \\{min_halfword}, because there's + a reference to \\{link}(\\{null}) in \\{try_break}. @115 +DX341. Initialize $\\{str_start}[0]\gets0$. @47 +IX342. Avoid blank space at beginning of line. @638 +DX343. Set type of new box in math mode to \\{ord_noad}, not \\{inner_noad}. @1076 +* 28 Sep 1982 +# Here are the first changes made to the preliminary listing of \TeX82 that was + published by the \TeX\ project earlier this month. +F520. Insert the missing cases \\{letter} and \\{other_char} after + \\{x_token} looks ahead. @1038 +C521. Change `|\pause|' to `|\pausing|'. @236 +D522. Reset \\{overfull_rule} when determining tabskip glue. @804 +A523. Fix the logic for scanning |\ifcase| [in obsolete syntax---everything + is still done with braces since `|\fi|' doesn't exist yet]. @509 +* 30 Sep 1982 +I524. Change |"0.0"| to |"?.?"| (suggested by DRF). @186 +* 2 Oct 1982 +Q525. Use conditional thin spacing next to `Inner' noads. @764 +Q526. Make thick spaces conditional. @766 +* 4 Oct 1982 +P527. Increase \\{trie_size} from 7000 to 8000, because of Frank Liang's improved + (but longer) hyphenation patterns. @11 +* 6 Oct 1982 +F528\>X330. Change the string lengths to match the new \\{\TeX_format_default}. @520 +# Version 0 of \TeX\ is being released today! +* 8 Oct 1982 +B529. Fix a blunder: I decreased $h$ mod a quarterword when it should have + been decreased mod \\{trie_op_hash_size} (HWT). @944 +* 9 Oct 1982 +P530\>X258. Fix a typo (`|!|' not `|&|') in the |WEB| documentation. @524 +F531. Remember to call \\{initialize} if a different format was preloaded + (Max D{\'\i}az). @1337 +# Version 0.1 incorporates the above changes. +* 12 Oct 1982 +G532. Add the `|\immediate|' feature, by popular request. @1375 +# Version 0.2 incorporates this (somewhat extensive) change. +* 13 Oct 1982 +P533. Introduce new |WEB| macros so that \\{glue_ratio} is more easily changed. @109 +# I began writing {\sl The \TeX book\/} today: edited the old preface and + searched in the library for quotations. +* 14 Oct 1982 +B534. Change the type of \\{hd} to \\{eight_bits}; it's + not a \\{quarterword} (HWT). @649 +S535\>X281. Revise the optimization of\/ |DVI| commands: It's not always safe to eliminate + \\{pop} when the preceding byte is \\{push}, since |DVI| commands + have variable length! (Embarrassing oversight caught by DRF.) @601 +* 15 Oct 1982 +C536. Test `$\\{prev_depth}>\\{ignore_depth}$', not `$\ne$'. @679 +# Version 0.3 incorporates the above changes. +* 16 Oct 1982 +P537. Omit definition of \\{align_size}; it's never used (Bill Scherlis). @11 +I538. Inhibit error messages when packaging box 255. @1017 +* 21 Oct 1982 +A539\>X145. Subtract $\\{width}(q)$ from \\{page_goal}, don't add it to + $\\{page_so_far}[1]$. @1009 +# Version 0.4 incorporates the above changes. +* 22 Oct 1982 +P540. Increase the amount of lower (variable-size) memory from 12000 to 13000, + since the \TeX\ program listing now needs about 11500. [At this time + there still is a fixed boundary between upper and lower memory.] @12 +G541. Add a new parameter |\boxmaxdepth|. @1086 +# Version 0.5 incorporates the above changes. +* 26 Oct 1982 +B542. Fix an off-by-one error caught by Gabi Kuper and HWT. + (I forgot `${}+1$'). @1317 +B543. Fix the spacing of displayed control sequences: \\{print_cs} should base its + decision on $\\{cat_code}(p-\\{single_base})$, not $\\{cat_code}(p)$. @262 +# The |TRIP| test detected this bug, but I didn't notice. +* 27 Oct 1982 +S544. Set \\{math_type} before saying $\\{fetch}(\\{nucleus}(q))$, since + fetching can have a side effect. @752 +* 28 Oct 1982 +G545. Install a major change: Fonts now have identifiers instead of code letters. + Eliminate the `|\:|' primitive, and give corresponding new + features to `|\the|'. @209 +# Actually I began making these changes on October 26, but I needed two days + to debug them and to put Humpty Dumpty together again. +# At this time I'm also drafting macros for typesetting {\sl The \TeX book}. +# The above changes have been incorporated into Version 0.6. +* 30 Oct 1982 +# After years of searching, I've finally found a definitive definition of + the printer's point; and (unfortunately) my previous conjecture was + wrong. The truth is that $\rm83\,pc=35\,cm$, exactly; + so I am changing \TeX\ to conform. +C546. Revise unit definitions for the `real' printer's point. @458,617 +# Version 0.7 incorporates the above. +* 1 Nov 1982 +# Oops! Retract error \#546, and retract \TeX\ Version 0.7; + the source of my information about points was flaky after all. + My original suppositions were correct, + as confirmed by NBS Circular 570. +* 4 Nov 1982 +C547. Revise the definition of |dd|, conforming to the definitive value + shown me by Chuck Bigelow. @458 +R548\>545. Introduce ``frozen'' copies of + font identifiers, to be returned by |\the\font|, so that font + manipulation is more robust. @1257 +* 5 Nov 1982 +D549. Reset \\{looseness} and paragraph shape when beginning a |\vbox|. @1083 +* 6 Nov 1982 +D550. De-update \\{align_state} when braces are in constants. @442 +I551\>X294. Improve error recovery for bad alignments. @1127 +# Today I wrapped up Chapters 4 and 5. +* 8 Nov 1982 +G552. Give more power to |\let|: the right-hand side needn't be a control + sequence. @1221 +I553. Amend \\{show_context} to say + `$(\\{base_ptr}=\\{input_ptr})\lor{}$'; otherwise undefined control + sequences can be invisible in unusual cases (John Hobby). @312 +A554. Compute demerits more suitably by adding a penalty squared, instead of + adding penalties before squaring. @859 +# Previously a slightly loose hyphenated line followed by a decent line + was considered worse than a decent hyphenated line followed by + a quite loose line. +* 10 Nov 1982 +E555. Save a bit of buffer space by declaring \\{pool_file} only in + |INITEX|. @50 +* 11 Nov 1982 +I556. Introduce a new context indicator to clarify \TeX's scanning state: + A special type + called \\{backed_up} is distinguished from other kinds of \\{inserted} + lists; it is called `recently read' or `to be read again', while + others are called `inserted'. @314 +I557. Append a comment, `|treated as zero|', to the missing-number message. @446 +I558. Ignore the settings of\/ |\hfuzz| or |\vfuzz| if\/ |\hbadness| or |\vbadness| + is less than 100. @666,677 +* 13 Nov 1982 +# Major surgery on the program is planned for today, because of new ideas + suggested by correspondence with MDS and other macro writers. +G559. Introduce a new |\tokens| register; this will be useful and easy to add, + since \TeX\ already can handle |\everypar| and |\output|. @1227 +C560\>X34. Change \\{get_x_token} to \\{get_token} when scanning an optional + space; then a construction like + |\def\foo{...}\foo| won't complain that |\foo| is undefined. @443 +# This change was retracted when it was being debugged, because it could + cause \\{endv} to abort the job. Then it was re-established again + when I found that \\{endv} needed to be more robust anyway. + [But it was eventually rescinded again.] +G561. Make |\span| mean `expand' in a preamble. @782 +E562. Use three separate {\bf if\/} tests instead of + `$\land$' in the inner loop of \\{get_next}, to gain efficiency. @342 +R563. Introduce \\{get_r_token} so that assignments have uniform error + messages and so that frozen equivalents cannot be changed. @1215 +# I gave a few variables more mnemonic names as I made these changes. +C564. Move conditional statements from the semantics (`stomach') part of + \TeX\ to the syntax (`mouth') part, by introducing `|\fi|'. + Also introduce |\csname| and |\endcsname|. @372,489\hbox{--}500 +# This makes macros much more predictable and logical, but it is by far + the most drastic change ever made to \TeX. The program began to come + back to life only after three days of solid hacking. +# Several other things were cleaned up as part of this change + because it is now more natural to handle them differently. + For example, a null control sequence has now become more logical. +# The result of all this is called Version 0.8. +* 18 Nov 1982 +# Today I resumed writing Chapter 8. Tomorrow I'm $\,2^{14}$ days old! +* 21 Nov 1982 +F565. Declare $c$ as a local variable for hyphenation (DRF). @912 +E566. Omit the ``first pass'' and try hyphenations immediately, + if\/ |\pretolerance| is negative (suggested by DRF). @863 +R567. Don't ship out incredibly huge pages; they might foul up + |DVI| files. @641 +* 2 Dec 1982 +G568. Add new features |\everymath| and |\everydisplay|. @1139,1145 +G569. Add a new feature |\futurelet|. @1221 +# The changes above have been incorporated into Version 0.9 of TeX. +* 7 Dec 1982 +G570. Add a new |\endinput| primitive (suggested by FY). @362,378 +* 8 Dec 1982 +I571. Try \\{off_save}, if\/ |\par| occurs in restricted horizontal mode. + (This avoids embarrassment if \TeX\ says `type a command or + say |\end|', then when you type |\end| it says you can't!) + [However, I soon retracted this change.] @1094 +* 21 Dec 1982 +A572. Redefine |\relax| so that its \\{chr} field exceeds 127. (This facilitates + the test for end in \\{scan_file_name}.) @265 +F573\>566. Call \\{begin_diagnostic} when omitting + the first pass of line breaking. @863 +A574. Fix the logic of glue scanning: In |\hskip-1pt plus2pt| the minus should + apply only to the |1pt|. @461 +* 23 Dec 1982 +I575. Renumber the decimal codes in paragraph statistics for loose and tight + lines; they were ordered backwards. @817 +C576. Treat a paragraph that ends with leaders like a paragraph that + ends with glue. @816 +C577. Allow commas as alternates to radix points, for Europeans. @438 +C578. Change |\hangindent| to a normal dimension parameter. [It had been + a combination of\/ |\hangindent| and |\hangafter|, with special + syntax.] @247 +G579. Make |\prevgraf| accessible to users. @422,1244 +G580. Split |\clubpenalty| off from |\widowpenalty|. @890 +# I'm typing Chapter 14 while making these changes. +* 24 Dec 1982 +S581. Use \\{back_input} instead of {\bf goto} \\{reswitch} when + inserting |\par|, because |\par| may have changed. @1095 +* 25 Dec 1982 +# It's 10pm after a very Merry Christmas! +I582\>X328. Don't prompt for a new file name if\/ |\openin| doesn't find a file. @1275 +G583. Add a new |\jobname| primitive. @472 +I584. Give the user a way to delete the dollar sign, when \TeX\ decides + to insert one. @1047 +C585. Allow optional equals after |\parshape|, and implement |\the\parshape|. + @423,1248 +* 26 Dec 1982 +I586. Add an \\{if_line_field} to the condition stack entries, + so that more informative error messages can be given. @489 +D587\>549. Introduce a \\{normal_paragraph} procedure, since initialization is needed + also within |\insert|, |\vadjust|, |\valign|, |\output|. @1070 +* 27 Dec 1982 +G588. Give users access to |\pagetotal| and |\pagegoal|. (Analogous to + \#679 and \#585, but simpler.) @1245 +I589\>X199. Introduce |\tracingpages|, allowing users to see + page-optimization calculations. Also split |\tracingparagraphs| off from + |\tracingstats|. @987,1005,1011 +# The changes above have been incorporated into Version 0.91 of \TeX. +* 31 Dec 1982 +P590. Break the \\{build_page} procedure into two parts, by extracting + the section now called \\{fire_up}. [This is necessary because + some Pascal compilers, notably for IBM mainframes, cannot + deal with large procedures.] @1012 +S591\>564. Make |\ifodd1\else| legal by introducing \\{if_code}. @489 +Q592. Improve alignments when columns don't occur: Don't append null boxes + for columns missing before |\cr|, and zero out the tabskip + glue after nonpresent columns. @802 +I593. Make the error message about overfull alignment more intelligible. + @801,804 +# The changes above have been incorporated into Version 0.92 of \TeX82, + which was the last version of 1982, + completed at 11:59pm on December 31. +* 3 Jan 1983 +# Today I'm beginning to write Chapter 15, and + planning the |\output| routine of |plain.tex|. +C594\>X186. Change the logic of \\{its_all_over}; use \\{max_dead_cycles} + here too, instead of the fixed constant~100. @1054 +F595\>X34. Don't forget to \\{pop_nest} when an insert is empty. Also disallow + optional space after |\insert|$\,n\,$|{...}|. @1100 +* 4 Jan 1983 +C596\>541. Use the |\boxmaxdepth| that's declared inside a |\vbox| when packaging it. + @1086 +C597. Rename |\groupbegin| and |\groupend| as |\begingroup| and + |\endgroup|. @265 +G598\>594. Make |\deadcycles| accessible to users. @1246 +Q599. Base the split insertions on natural height plus depth, not + on \\{delta}. @1010 +# The changes above have been incorporated into Version 0.93. +* 6 Jan 1983 +D600. Add \\{push_math} to handle a case where I forgot + to clear \\{incompleat_noad}. (This long-standing bug was + unearthed today by Phyllis Winkler.) @1136 +G601\>588. Add |\pageshrink|, etc., too. @1245 +G602. Introduce new parameters |\floatingpenalty|, |\insertpenalties|. Also + adopt a new internal representation of insertion nodes, + so that |\floatingpenalty|, |\splittopskip| and |\splitmaxdepth| + can be stored with each insertion. @140,1008 +* 7 Jan 1983 +Q603. Improve the rules for entering \\{new_line}, in particular + when the end-of-line character is active. @343 +* 9 Jan 1983 +Q604. Distinguish between implicit and explicit kerns. @155,896 +C605. Change the name |\ignorespace| to |\ignorespaces|. @265 +C606\>560. Don't omit a blank space after |\def|, |\message|, |\mark|, etc.; + the previous hodge-podge of rules is impossible to learn. @473 +# The above changes appear in Version 0.94. +* 12 Jan 1983 +# Beginning to write the chapters on math today. +G607. Add a new feature: active characters in math mode. @1151 +* 15 Jan 1983 +A608. Fix a surprise bug: `|$1-$|' treated the |-| as binary. @729 +D609. Initialize \\{space_factor} inside discretionaries. @1117 +* 16 Jan 1983 +F610. Fix an incredibly embarrassing bug: I forgot to update \\{spotless} in the + \\{error} routine! +# While fixing this, I decided to change + \\{spotless} to a more general \\{history} variable, as suggested + by IBMers who want a return code. @76,82,1335 +I611. Replace two calls of \\{confusion} by attempts at error recovery, in places + where `|This can't happen|' could actually happen. @1027,1372 +* 18 Jan 1983 +R612. Introduce the \\{normalize_selector} routine + to protect against startup anomalies + when the transcript file isn't open. Also make \\{open_log_file} + terminate in some cases. @92,535 +R613\>591. Insert |\relax|, not a blank space, to cure infinite + loop like |\ifeof\fi| (LL). @510 +G614. Change the old |\limitswitch| to |\limits|, |\nolimits|, and + |\displaylimits|. Incidentally, this fixes a bug in the former + positioning of integral signs. @682,749 +C615. Give a |\char| in math mode its inherited |\mathcode|. @1151 +Q616\>525. Make underline, overline, radical, vcenter, accent noads and |{...}| + all revert to type Ord instead of type Inner. Introduce a new primitive + |\mathinner|. (This fixes the spacing, which + got worse in some ways after change \#525.) @761 +# I'm working on Appendix G today. +* 19 Jan 1983 +G617. Introduce a |\mathchoice| primitive. @1174 +C618. Move |\input| from the stomach to the mouth. @378 +C619\>X260. Introduce |\chardef|, analogous to |\mathchardef|. @1038,1224 +G620. Change |\unbox| to |\unhbox| and |\unvbox|; also add |\unhcopy|. @1110 +C621. Consider |\spacefactor|, |\pagetotal|, etc., as part of + \\{prefixed_command}, even though they are always global. @1211 +* 20 Jan 1983 +C622. Switch modes when |\hrule| occurs in horizontal mode or |\vrule| + in vertical. @1090,1094 +G623. Add a new |\globaldefs| feature. @1211 +* 21 Jan 1983 +E624. Optimize the code, in places where it's important (based on + frequency counts of \TeX\ usage + accumulated during the past week): Introduce \\{fast_get_avail} + and \\{fast_store_new_token}; reduce procedure-call overhead + in \\{begin_token_list}, \\{end_token_list}, \\{back_input}, + \\{flush_node_list}; change some tests from `{\bf if} $a\land b$' to + `{\bf if}~$a$ {\bf then if}~$b$'. @122,371 +* 22 Jan 1983 +E625. Save space in math lists: Don't insert penalties within restricted + horizontal mode; simplify trivial boxes. @721,1196 +S626. Fix a surprising oversight in the \\{rebox} routine: + Ensure that $b$ isn't a vbox. @715 +C627\>545. Make |\nullfont| a primitive, so that \\{cur_font} always + has a value. (This is a dramatic improvement over \TeX78, where a + missing font was a fatal error called `|Whoa|'!) @552 +* 24 Jan 1983 +I628\>586. List all incomplete |\if|'s when the job ends. @1335 +* 29 Jan 1983 +C629\>552. Change initialization of \\{align_state} so that |\halign\bgroup| + works. @777 +* 30 Jan 1983 +D630\>625. Be sure to test `\\{is_char_node}($q$)' when checking for a trivial + box. @721 +# By extraordinary coincidence, this bug was caught when somebody + used font number~11 ($=\\{kern_node}$) in the second character + of a list of length~2! +I631\>X168. Improve format for stats at end of run, as suggested by DRF. @1334 +# The changes above have been incorporated into Version 0.95. +C632. Don't ignore the space after a control symbol (except `|\ |'). @354 +P633. Remove all trailing spaces at the right of input lines, + so that there's perfect compatibility with IBM systems that + extend short lines with spaces. @31 +* 3 Feb 1983 +I634. Assume that a \\{math_accent} was intended, after giving an error + message in the case $\\{mmode}+\\{accent}$. @1165 +G635. Add new primitives |\iftrue| and |\iffalse|. @488 +* 6 Feb 1983 +A636\>X304. Improve the accuracy of fixed-point arithmetic when + calculating sizes for |\left| and |\right|. (I had started by + dividing \\{delimiter_factor}, not \\{delta1}, by 500.) @762 +* 12 Feb 1983 +C637. Change the name |\delimiterlimit| to |\delimitershortfall|. @248 +C638. Make |\abovewithdelims..| equivalent to |\above|; change the + order of operands so that delimiters precede the dimension. @1182 +C639\>607. Remove the kludgy math codes introduced earlier; + make |\fam| a normal integer parameter and allow |\mathcode| + to equal $2^{15}$. @1233 +R640. Don't let |\spacefactor| become more than $2^{15}$. @1233,1243 +# I finished drafting Chapter 17 today. +* 14 Feb 1983 +I641\>639. Replace octal output (\\{print_octal}) by hexadecimal (\\{print_hex}) + so that math codes are clearer. @67 +F642\>619. Don't forget \\{char_given} in the \\{math_accent} routine. @1124 +* 17 Feb 1983 +C643\>622. Switch modes when |\halign| occurs in horizontal mode, or |\valign| + in vertical mode. @1090,1094 +* 18 Feb 1983 +I644. Add a new feature |\tracingrestores|. This requires a new procedure called + \\{show_eqtb}, whose code can be + interspersed with the \\{eqtb} definitions. @252 +* 25 Feb 1983 +I645\>622. Suggest using |\leaders| when the user tries a horizontal rule + in restricted horizontal mode. @1095 +* 27 Feb 1983 +I646. Specify the range of source lines, when giving warning messages + for underfull or overfull boxes in alignments. @662,675 +# Why did it take me all day to type the middle part of Chapter 18? +* 4 Mar 1983 +G647. Introduce a new feature |\xcr| (suggested by LL). [Changed later to + `|\crcr|'.] @785 +I648\>631. Subtract out \TeX's own string requirements from the stats. @1334 +* 6 Mar 1983 +G649. Add new features |\everyhbox| and |\everyvbox|. @1083,1167 +* 9 Mar 1983 +R650\>X295. Avoid accessing \\{math_quad} when the symbol fonts aren't known + to be present. @1199 +P651\>533. Introduce \\{float} and \\{unfloat} macros to aid portability (HWT). @109 +C652. Introduce new names |\abovedisplayskip| and |\belowdisplayskip| for + the old |\dispskip|; also |\abovedisplayshortskip| and + |\belowdisplayshortskip| for the old |\dispaskip| and |\dispbskip|. @226 +* 10 Mar 1983 +C653. Unbundle |\romannumeral| from |\number| (suggested by FY). @468 +* 12 Mar 1983 +C654. Ignore leading spaces in \\{scan_keyword}. @407 +* 14 Mar 1983 +E655\>631. Use \\{write} and \\{write_ln} directly when printing stats. @1334 +* 16 Mar 1983 +Q656\>602. Refine the page-break cost function (introducing `\\{deplorable}', + which is not quite `\\{awful_bad}'), after suggestion by LL. @974,1005 +# The changes above have been incorporated into Version 0.96. +* 18 Mar 1983 +G657. Add a new feature |\everyjob| suggested by FY. @1030 +* 19 Mar 1983 +I658. Don't treat left braces specially when showing macros. @294 +C659. Ignore blanks that would otherwise become undelimited arguments. @393 +* 21 Mar 1983 +F660\>X280. Make |\lastskip| handle \\{mu_glue} as well as ordinary glue. @424 +C661\>561. Expand only one level in a preamble |\span|. @782 +* 22 Mar 1983 +C662. Let a single |#| suffice in |\tokens|, |\message|, etc. (The previous rule, + in which |##| was always required as in macros, was a loser especially + in |\write| where you had to say |####|!) @477 +C663\>X328. Require the keyword `|to|' in |\read|. (This will avoid the common error + of an incomplete constant when no space appears + before the |\cs|.) Also allow terminal + I/O as a default when a stream number is out of range. @482,1225,1370 +* 26 Mar 1983 +C664. Replace |\ifeven|\<countnumber> by |\ifodd|\<number>, for better + consistency of language. @504 +S665\>564. Introduce the \\{change_if_limit}, to overcome a big surprise + bug relating to |\if\if aabc\fi|. @497 +# Such examples show that \\{cur_if} might not be current, + in my original implementation. +* 28 Mar 1983 +G666\>X326. Tolerate non-characters as arguments to |\if| and |\ifcat|. @506 +C667. Change `|absent|' to `|void|', a better word. @487 +C668. Clear the \\{shift_amount} in |\lastbox|, since I don't + want to figure out what it means in all cases. @1081 +* 29 Mar 1983 +I669. Wake up the terminal before giving an error message. (This + means a special \\{print_err} procedure is introduced.) + (Suggested by DRF.) @34,73 +* 1 Apr 1983 +# Today I finished Chapter 21 (boxes) and began to draft Chapter 22 (alignments). +G670. Allow periodic preambles in alignments. @793 +C671. Make |\leaders| line up according to the smallest + enclosing box. @627,636 +Q672. Allow hyphenation after whatsits (e.g., after items for an index). @896 +* 2 Apr 1983 +Q673. Call \\{build_page} when |\par| occurs in vertical mode. @1094 +C674. Clear \\{aux} in \\{init_row}, for tidyness. @786 +* 4 Apr 1983 +C675. Let digits switch families in math mode. @232 +* 7 Apr 1983 +Q676\>602. Refine the test for not splitting an insertion. @1008 +* 8 Apr 1983 +C677\>647. Rename |\xcr| as |\crcr|, at LL's request. @780 +* 9 Apr 1983 +# Took a day off and had a chance to help print a sample page on + a 150-year-old letterpress in Murphys, California. +* 11 Apr 1983 +I678. Recover more sensibly after a runaway preamble. @339 +* 12 Apr 1983 +C679\>X328. Make |\read| span several input lines, if necessary to get + balanced braces. @482 +* 14 Apr 1983 +S680. Fix a subtle bug found by JS: \S882 can make $q$ a \\{char_node}, + so we need to test `{\bf if} $\lnot\\{is_char_node}(q)$'. + [Actually I discovered much later that the real bug was + to omit `{\bf else}' at this point.] @881 +* 15 Apr 1983 +C681. Make |\uppercase| and |\lowercase| apply to all characters, regardless + of category. @1289 +# 7:30am. After working all night, I completed a draft of the manual thru + Chapter 22, for distribution to volunteer readers. +# 5pm. The changes above have been incorporated into Version 0.97. +* 17 Apr 1983 +R682. Change `\\{small_number}' to `$0\,.\,.\,65$' in the + hyphenation routine (DRF). @901 +I683. Flush patterns in the input when the user tries |\patterns| + outside of\/ |INITEX| (suggested by DRF). @1252 +# Tomorrow I fly to England, where I'll lecture and write a paper about + `Literate Programming' [{\sl Comp.~J. \bf27} (1984), 97--111]. +* 14 May 1983 +I684\>663. Improve the behavior of\/ |\read| from terminal + (suggested by Todd Allen at Yale). + [I'd forgotten to implement the extended stream numbers in \#663. + Also, the prompt is now omitted if $n<0$.] @484 +* 18 May 1983 +I685. Restrict |\write| $n$ to the transcript file only, if $n<0$. @1350 +C686\>X188. Unify the syntax for registers and internal quantities. (Remove + primitives called `|\insthe|' and `|\minusthe|'; rename + \\{scan_the} to \\{scan_something_internal}, and change its + interface accordingly; clean up command codes generally.) @209,413 +G687. Introduce new parameters |\hoffset|, |\voffset|. @617 +* 24 May 1983 +G688. Introduce a new parameter |\everycr| (suggested by MDS). @774,799 +# Many macro writers and preliminary-manual readers have been requesting + new features; I'll try to keep the language as concise and consistent + as possible. +* 25 May 1983 +G689. Introduce |\countdef|, |\dimendef|, etc.\ (suggested by DRF long ago, + easy now in view of \#686). @1224 +G690. Introduce |\advance|, |\multiply|, |\divide| (suggested by FY). @1240 +G691. Introduce |\hyphenchar|; this requires a new command + \\{assign_font_int}, plus minor changes to about 15 modules. @915 +G692. Introduce |\skewchar| (easy because of \#691). @741 +G693. Introduce |\noexpand|. (I had difficulty thinking of how to + implement this one!) @358,369 +G694. Introduce |\meaning|. @296 +G695\>X231. Remove `|dm|' and `|vu|'; allow the more general `|.5\hsize|'. @455 +C696. Change `|\texinfo| $f$ $n$' to `|\fontdimen| $n$ $f$'. @578 +* 27 May 1983 +G697. Add a new feature |\afterassignment| (suggested by ARK). @1269 +C698\>619. Adjust the timing so that commands like `|\chardef\xx=5\xx|' + behave sensibly. @1224 +* 28 May 1983 +C699. Ignore `|\relax|' as if it were a space, in math mode and in a few other + places where |\relax| would otherwise be erroneous. @404 +Q700. Improve |\mathaccent| spacing with respect to subscripts + and superscripts (suggested by HWT). @742 +* 30 May 1983 +C701\>598. Terminate a job only when $\\{dead_cycles}=0$. @1054 +# The changes above constitute Version 0.98. +* 3 Jun 1983 +# I finished the draft of Chapter 23 (output routines) today. +G702. Allow |\mark| and |\insert| and |\vadjust| in restricted + horizontal mode, and also in math mode. (This is a comparatively + big change, triggered by the fact that |\mark| in a display + presently causes \TeX\ to crash with `|This can't happen|'!) + The global variable \\{adjust_tail} is introduced. @796,888,1085 +* 6 Jun 1983 +G703\>695. Replace (and generalize) the previous uses of\/ |ht|, |wd|, and |dp| + in dimensions by introducing the new control sequences + |\ht|, |\wd|, and |\dp|. @1247 +I704. Display sub-parts of noads with the symbols |^| and |_| instead of + |(| and~|[|. @696 +C705\>694. Allow |A..F| in hex constants to be \\{other_char} as well as + \\{letter}. @445 +* 7 Jun 1983 +E706\>654. Remove an instance of \<Scan optional space>, since it's now + redundant. @457 +C707. Legalize |\mkern\thinmuskip| and |\mkern5\thinmuskip|. @456 +C708. Clean up the treatment of optional spaces in numerical specifications. @455 +# A construction like |2.5\space\space\dimen0| was previously + valid after `|plus|' or `|minus|' only! +# I'm obviously working on Chapter~24 today. +C709\>545. Allow `|\font|' as a \<font identifier> for the current font. @577 +C710\>623. Don't make |\gdef| global when $\\{global_defs}<0$. @1218 +E711. Produce \\{zero_glue} as the outcome of + |\advance\spaceskip by-\spaceskip|. @1229 +I712. Make |\show| do something appropriate for every possible token. @1294 +G713\>559. Replace the (single) |\tokens| parameter by an array of + 256 token registers. @230 +C714. Allow |\indent| in math mode; also make |\valign| in math mode produce the + `|Missing|~|$|' error. @1046,1093 +E715. Remove redundant code: There's no need to check \\{cur_group} + or call \\{off_save} when starting alignments or equation numbers + in displays. @1130,1142 +* 8 Jun 1983 +C716. Disallow |\openout-1| and |\closeout-1|. @1350 +C717. Disallow |\lastbox| in math mode. @1080 +* 9 Jun 1983 +I718. Call \\{back_error}, not \\{error}, when |\leaders| aren't followed by + proper glue. @1078 +D719. Initialize for a possible paragraph, after |\noalign| + in a |\valign|. @785 +* 10 Jun 1983 +C720\>708. Expand the optional space after an ASCII constant. @442 +* 12 Jun 1983 +C721. Set $\\{space_factor}\gets1000$ after a rule or a + constructed accent. @1056,1123 +* 14 Jun 1983 +D722. Correct a serious blunder: Set $\\{disc_width}\gets0$ before testing + if $s$ is null (caught by JS). @869 +# This is a real bug that existed since the beginning! + It showed up on page~37 of the + Version~0 |TRIP| manual, but I didn't notice the problem. +C723\>708. Make optional spaces after \<dimen> like those after \<number>. @448 +C724\>568. Insert \\{every_display} before calling \\{build_page}. @1145 +I725\>648. Report \TeX's capacity on overflow errors in a way that's + fully consistent with other statistical reports. @42 +* 17 Jun 1983 +C726. Make all |\tracing| decisions on the basis of $\ge$ versus $<$, + not $\ne$ versus~$=$. @581 +# Today I finished the draft of Chapter 27 (the last chapter)! +# The changes above were released as Version 0.99 on June 19, 1983. +* 20 Jun 1983 +C727. Set |\catcode`\%=14| in |INITEX|. @232 +C728\>587. Call \\{normal_paragraph} when |\par| occurs in vertical mode. @1094 +# Once again I'm retiring about 8am and awaking about 4pm. +* 21 Jun 1983 +C729\>558. Don't append an overfull rule solely because of\/ |\hbadness|. @666 +R730. Don't allow the glue-ratio of shrinking to be less than~$-1$. @810,811 +* 22 Jun 1983 +B731\>653. Declare the parameter to \\{print_roman_int} to be of type \\{integer}, + instead of \\{nonnegative_integer} (found by Debby Clark). @69 +C732\>690. Make the keyword `|by|' optional (suggested by LL). @1236 +* 24 Jun 1983 +I733. Say `|preloaded|' when announcing \\{format_ident}. @1328 +* 25 Jun 1983 +R734. Add extra boxes and + glue to the output of alignment. [This thwarts possible attempts + at trickery by which system-dependent glue set values + computed by |\span| could have gotten into \TeX's registers by + things like |\valign| and |\vsplit|. It also has the advantage + of perfect accuracy in alignment of vertical rules.] @809 +C735. Make leaders affect the height or width of the enclosing boxes. @656,671 +# Today I'm mainly installing a much-improved format for change files + in |WEB| programs (suggested by DRF). +* 28 Jun 1983 +C736. Permit |\unskip| in vertical mode when we know that it does nothing. @1106 +* 1 Jul 1983 +E737\>700. Avoid redundant boxes when things like `|{\bf A}|' occur in math. @1186 +G738. Add a `|scaled|' feature to |\font| input. @1258 +D739\>700. Remember to correct \\{delta} when an accented box changes. @742 +* 2 Jul 1983 +R740.Introduce \\{bypass_eoln}, to remove anomalous behavior on input files + of length~1. (Suggested by DRF after the problem was discovered by LL). @31 +* 4 Jul 1983 +G741. Allow codes like |^^b| as well as |^^B|. @352,355 +G742. Introduce new parameters |\escapechar|, |\endlinechar|, |\defaulthyphenchar|, + and |\defaultskewchar|, to make \TeX\ less dependent on the + character set. (This affects many modules, since a lot of + error messages must be broken up so that they use \\{print_esc}.) +* 7 Jul 1983 +P743. Use a system-dependent function \\{erstat} when opening or closing + files (suggested by DRF). @27 +* 11 Jul 1983 +# The computer is back up after more than 50 hours down time + (due to air conditioning failure). +I744. Show total glue in the output of\/ |\tracingpages|. @985 +R745. Guard against insertion into an hbox. @993 +C746. Legalize the assignment \<tokenvar>=\<tokenvar>. @1227 +I747. Introduce a new parameter |\errhelp|. @1283 +F748\>623. Don't forget to check \\{global_defs} when |\tabskip| is changed. @782 +* 12 Jul 1983 +C749. Allow an |\outer| macro to appear after |\string|, |\noexpand|, + and |\meaning| (Todd Allen). @369,471 +C750. Make `|\the|' an expandable control sequence (i.e., move it + from the stomach to the throat); this cleans up + several annoying glitches. @367 +C751\>620. Allow |\unhbox| and |\unhcopy| in math mode if the box is void. @1110 +* 13 Jul 1983 +# I lectured for four hours at the TUG meeting today after very little sleep! +* 16 Jul 1983 +# The following were suggested by TUG meeting discussions. +L752. Round the value of \\{default_rule} more properly: It should be 26215. @463 +Q753\>700. Fix |\mathaccent| again; it's still not right! + The final height should be the maximum of + the height of accented letter without superscript and + the height of unaccented letter with superscript. @742 +G754. Add a new feature |\newlinechar|. @59 +G755. Allow boxes and rules in discretionaries (suggested by somebody + from Hewlett-Packard). @1121 +I756\>X28. Show all token expansions, not just macros, + when |\tracingcommands|. @367 +C757. Allow |\char| in a |\hyphenation| list. @935 +G758. Introduce a new feature |\aftergroup|; it can be implemented with + \\{save_stack}. @326 +C759. Run the running dimensions to alignment boundaries (suggested + by ARK). @806 +* 17 Jul 1983 +R760. Zero out \\{hyf} values at the edges, so that + weird pattern data cannot lead to Pascal range checks. @965 +R761\>X190. Decrease the |hc| codes for hyphenation, so that code~127 cannot + possibly be matched. @937,962 +C762\>672. Allow whatsits after hyphenatable words. @899 +C763\>604. Represent an italic correction as an explicit kern. @1113 +* 18 Jul 1983 +C764. Allow lowercase letters in file names. @519 +I765. Change the message `|No output file|' to: `|No pages of output|'. @642 +I766. Confirm that a quiet mode is being entered, when error + interaction ends with |Q|, |R|, or |S| (suggested by ARK). @86 +# Version 0.999 was finally installed today; a new program listing has + been printed. +# From now on, I plan to keep all section numbers unchanged. +# I'm done writing Appendix~H; beginning to revise Chapter~20. +* 25 Jul 1983 +C767\>663. Allow space after `|to|' in the |\read| command (FY). @1215 +# To bed at 1pm today. +* 27 Jul 1983 +S768\>665. Stack the current type of\/ |\if|; this precaution is necessary + in general (FY). @498 +# To bed at 2pm today. +* 29 Jul 1983 +E769. Avoid putting a control sequence in the hash table + when it occurs after |\ifx|. (Requested by Math Reviews people.) @507 +# Finished a version of {\sl The \TeX book\/} lacking only Appendices + D, E, and~I, for distribution to interested readers. +# To bed at 10:30pm, planning to arise regularly at 6am for a change. +* 31 Jul 1983 +I770\>766. Call \\{update_terminal} when going quiet (HWT). @86 +* 1 Aug 1983 +C771. Don't put an empty line at the end of an |\input| file! (This simplifies + the rules and the program, and also gets around a bug that occurred + at the end of files with $\\{end_line_char}<0$.) @362 +# The changes above went into Version 0.9999, which was widely distributed. +* 16 Aug 1983 +B772\>665. Rectify a ridiculous gaffe: I initialized $q$ every time the loop + of \\{change_if_limit} was performed! (Found by FY.) @497 +I773\>648. Distinguish `|string|' from `|strings|' when reporting statistics. @1334 +A774. Introduce \\{lx}, to correct a bug in |\xleader| computations + (found by FY). @627 +* 20 Aug 1983 +F775. Don't forget to apply |\/| to ligatures. @1113 +# Today I began to read all previous issues of {\sl TUGboat}, in preparation for + Appendix~D. +* 27 Aug 1983 +I776. Add debugging hack number~16, to help catch subtle data structure bugs. @1339 +E777. Remove redundant setting and resetting of \\{name_in_progress}. @531 +S778\>618. Suppress |\input| during a font size spec; otherwise + \\{cur_name} is clobbered (found by MDS). @1258 +G779. Introduce new conditionals |\ifhbox| and |\ifvbox|. @505 +* 29 Aug 1983 +D780\>750. Test for an empty list, if emptiness will mess up the data structure. + (Found by Todd Allen.) @478 +E781\>624. Use \\{fast_store_new_token} in another place for efficiency. @466 +I782. Say `|has only|' instead of `|has|'. @579 +# These changes yield Version 0.99999, used only at Stanford. +* 30 Aug 1983 +C783. Make funny blank spaces showable. @298 +* 31 Aug 1983 +C784\>754. Make |\newlinechar| affect \\{print_char}, not just \\{print}. @58 +* 4 Sep 1983 +G785. Add new features |\lastkern|, |\lastpenalty|, |\unkern|, |\unpenalty|. + @424,996,1105 +# OK, Appendix D is finished!! +# The above changes have been installed in Version 0.999999. +* 17 Sep 1983 +P786\>548. Don't bother making duplicate font identifiers; that + was overkill, not really needed. @1258 +# Will this be the historic last change to \TeX? +* 18 Sep 1983 +I787. Correct a minor inconsistency, `|display|' not `|displayed|'. @211 +* 20 Sep 1983 +C788\>604. Treat the kerns inserted for accents as explicit kerns. @1125 +* 26 Sep 1983 +I789. Change `|log|' to `|transcript|' in several messages. @535,1335 +# The index was finished today; I mailed the entire {\sl \TeX book\/} to + Massachusetts for final proofreading before publication. +* 1 Oct 1983 +D790. Prevent uninitialized trie positions in case of overflow + (found by Bernd Schulze). @944 +* 7 Oct 1983 +# Henceforth our weekly `\TeX\ lunch' meetings will be called `\MF\ lunch'. +# DRF begins to produce {\sl The \TeX book\/} on our APS phototypesetter. +* 14 Oct 1983 +P791\>633. Ignore spaces at the ends of lines also in |TEX.POOL| (found + by DRF). @52 +D792\>610. Initialize the \\{history} variable at \\{start_here} (DRF). @1332 +* 18 Oct 1983 +I793. Extend \\{runaway} to catch runaway text (suggested by FY). @306 +D794. Reset \\{cur_cs} after \\{back_input}, not after scanning the + `|=|' (found by FY). @1226 +* 24 Oct 1983 +I795\>638. Change the error recovery for bad delimiters, in accordance with + the changed syntax. (Found by Barry Smith.) @1183 +* 9 Nov 1983 +E796. Optimize the code a bit more, based on empirical frequency data gathered + during September and October: In \S45, use the fact that the + result is almost always true. In \S380, delete `{\bf while} + \\{true} {\bf do}' since many compilers implement that badly. + Rewrite \S852 to avoid calling \\{badness} in the most common case. + @45,380,852 +* 3 Dec 1983 +F797. Don't forget to call |error| after the message has been + given (noticed by Gabi Kuper). @500 +# Version 1.0 released today incorporates all of the above. +* 9 Dec 1983 +# Dinner party with 36 guests to celebrate \TeX's coming of age. +* 2 Feb 1984 +S798\>786. Reinstall |\font| precautions that I thought were unnecessary. + I overlooked many problematic possibilities, like + `|{\font\a=x| |\global\a}| |\the\font|' + and `|\font\a=x| |\font\b=x| |\let\b=\undefined| |\the\a|', etc. + (Found by Mike Urban.) The new remedy involves removal of the + \\{font_ident} array and putting the identifiers into a frozen + part of the hash table; so there's a sprinkling of corrections + in lots of modules. But basically the change is quite conservative, + so it shouldn't spawn any new bugs (it says here). @222,267,1257 +* 9 Feb 1984 +S799. Remove the possibility of double interrupt, in a scenario + found by Clint Cuzzo. @1031 +* 12 Feb 1984 +Q800. Improve spacing in a formula like |$(A,<)$|. @764 +* 13 Feb 1984 +A801. Avoid a bad {\bf goto}, as diagnosed by Clint Cuzzo and George O'Connor. + (Must not go directly to \\{switch}.) @346 +E802. Conserve string pool space by not storing file name in two + guises (suggested by DRF). @537 +* 26 Feb 1984 +I803. Make scaled output look cleaner by printing fewer decimals whenever + this involves no loss of accuracy. (Suggested by \MF\ development.) @103 +* 2 Mar 1984 +R804. Maintain 17-digit accuracy, not 16; now + constants like `|.00000762939453126pt|' will round correctly. @452 +* 16 Mar 1984 +R805. Plug a loophole that permitted recursion in \\{get_next}, by disallowing + deletions in \\{check_outer_validity}. @336 +* 24 Mar 1984 +I806. Open the terminal before trying to wake it up, when the program starts bad. + @1332 +* 27 Mar 1984 +R807. Check that $k<63$, to avoid the + |\patterns{xxx...xxxdxxxdxxx}| anomaly found by Jacques D\'esarm\'enien. @962 +* 11 Apr 1984 +F808. Supply code for the missing case \\{adjust_node} in \\{copy_node_list}. @206 +# Yoicks, how could serious bugs like that have escaped detection? +* 11 Jun 1984 +D809\>627. Initialize \\{char_base}, etc., for \\{null_font}. + (Found by Nick Briggs.) @552 +R810. Clear the \\{buffer} array initially (Briggs). @331 +* 21 Jun 1984 +C811. Look ahead for ligature or kern after a |\chardef|'d item + (D\'esarm\'enien). @1038 +* 4 Jul 1984 +R812. Make the quarterword constraint explicit with a + new `\\{bad}' case (19). @111 +* 7 Jul 1984 +E813. Optimize \\{firm_up_the_line} slightly, + to be consistent with the \MF\ program. @363 +* 8 Jul 1984 +I814. Give additional diagnostics when |\tracingmacros>1|. @323 +# The changes above were incorporated in Version 1.1, released July 9, 1984. +* 27 Jul 1984 +I815. Say `|see| |the| |transcript| |file|' after handling offline |\show| + commands. (Suggested by \MF.) @1298 +* 20 Oct 1984 +I816. Allow `|0|' in response to error prompts. @84 +# Those two changes led to Version 1.2. +* 25 Nov 1984 +R817. Don't forget to check for \\{null} before looking at subfields + of a node. (This was ``dirty Pascal,'' with two quarterword 0's + read as a halfword.) @846 +R818. Ditto in another place! @939 +E819. Remove the fixed-at-compile-time + partition between lower and upper memory. @116,125,162 +# This major change in memory management + completes Version 1.3, which was published in preliminary + looseleaf form as `\TeX: The Program'. +* 20 Dec 1984 +R820. Keep the \\{node_size} field from overflowing if the lower part of memory + is too large. @125 +# That was another bug in existence from the beginning! +* 5 Jan 1985 +I821. Improve the missing-format-file error (DRF). @524 +* 7 Jan 1985 +I822. Update the terminal right away so that the welcoming message will + appear as soon as possible (DRF). @61 +* 23 Jan 1985 +I823. Convey more uncertainty in the + help message at times of \\{confusion}. @95 +I824\>610. Improve the \\{history} logic in the \\{warning_issued} case. @245 +* 18 Feb 1985 +P825\>810. Stick to standard Pascal: Don't + use \\{first} in a {\bf for} loop. [Some procedures ``threaten'' it + globally, according to British Standard 6192, section 6.8.3.9.] + (Pointed out by CET.) @331 +* 11 Apr 1985 +S826. Prevent nonexistent characters from being output by + unusual combinations of ligatures and hyphenation. @915 +* 15 Apr 1985 +L827\>819. Compute memory usage correctly in |INITEX|; the previous number + was wrong because of a |WEB| text macro without parentheses (DRF). @164 +* 16 Apr 1985 +E828. Speed up \\{flush_list} by not calling \\{free_avail} (DRF). @123 +* 17 Apr 1985 +A829\>788. Introduce a special kind of kern for accent positioning; + it must not disappear after a line break. @837,879,1125 +* 18 Apr 1985 +R830\>755. Prevent |\lastbox| and |\unkern| from removing discretionary replacements. + @1081,1105 +# That completes Version 1.4. +* 26 Apr 1985 +C831. Don't try \\{\TeX_area} if a nonstandard file area has been specified + (DRF). @537 +# That was \#401 in \TeX78; I never learn! +* 30 Apr 1985 +C832\>754. Eliminate the limitation on |\write| length; the reason for it + has disappeared (Nancy Tuma). @1370 +* 8 May 1985 +D833\>819. Allocate two words for the head of the \\{active} list (CET). @162 +* 11 May 1985 +I834. Change \\{wterm} to \\{wterm_ln} after a bad beginning (Bill Gropp). @1332 +E835\>806. Don't open the terminal twice (CET). @1332 +* 22 May 1985 +R836. Test for \\{batch_mode} after trying to open the transcript file, + not before (DRF). @92 +R837. Be prepared for string pool overflow while reading the command line! + (This bug was first found in \MF, when it could occur more easily.) @525 +* 7 Aug 1985 +A838. Fix a bug in |\edef\foo{\iffalse\fi\the\toks0}|: \TeX\ should stay in the + loop when expanding non-|\the|. (Found by Dan Brotsky.) @478 +# The above changes were incorporated in Version 1.5. +* 27 Nov 1985 +C839\>764. Make `|plain|' a lowercase name, for consistency with the manual. @521 +I840\>669. Wake up the terminal for |\show| commands. @1294,1297 +# The above changes were incorporated in Version 2.0, which was published + as Volume~B of the {\sl Computers \& Typesetting\/} series. +* 15 Dec 1986 +I841. Punctuate the Poirot help message more carefully. @1283 +* 28 Jan 1987 +R842. Make sure that \\{max_in_open} doesn't exceed 127 (DRF). @14 +D843\>680. Don't allow a |\kern| to be clobbered at the end of a pre-break list + when a discretionary break is taken. (A missing `{\bf else}' was the + source of the error, diagnosed incorrectly before.) @881 +D844. Take account of discarded nodes when computing the background width + after a discretionary. @840 +# That was the first really serious bug detected for more than 17 months! I found it + while experimenting with right-to-left extensions. +# Version 2.1 was released on January 26, 1987. +* 5 Feb 1987 +E845. Remove cases in \\{shorthand_def} that cannot occur (found by Pat Monardo). @1224 +* 14 Apr 1987 +R846. Improve robustness of data structure display + when debugging (Ronaldo Am\'a). @174,182 +* 21 Apr 1987 +E847. Make the storage allocation algorithm more elegant and efficient. @127 +* 22 Apr 1987 +A848\>742. Calculate the empty-line condition properly when \\{end_line_char} is + absent. @360 +# The previous three changes were found while I was teaching a class based + on Volume~B; they led to Version 2.2. +* 28 Apr 1987 +E849. Avoid closing a file when \TeX\ knows that it isn't open (JS). @560 +* 3 Aug 1987 +S850. Clean up unfinished output if it's necessary to + \\{jump_out} (Klaus Gunterman). @642 +# That makes Version 2.3; subsequent version numbers won't be logged here. +* 19 Aug 1987 +A851. Indent rules properly in cases like\hfil\break + |\hangindent=1pt$$\halign{...\cr\noalign{\hrule}}$$|. @806 +* 20 Aug 1987 +S852. Introduce \\{co_backup} because of cases like + |\hskip 0pt plus 1fil\ifdim| (Alan Guth). @366 +* 9 Nov 1987 +S853. Change the calculation for number of leader boxes, so that + it won't be too sensitive to roundoff error near exact multiples + (M. F. Bridgland). @626 +* 17 Nov 1987 +A854. Replace my stupid algorithm + for fixed-point multiplication of negatives (WGS). @572 +* 12 Dec 1987 +B855. Fix a typo in the initialization of hyphenation tables (PB). @952 +# That error was almost completely harmless, thus undetectable, + except if some |\lccode| is~1 and no |\patterns| are given. +* 23 Dec 1987 +S856\>564. Be more cautious when ``relaxing'' a previously undefined |\csname|; + you might be inside a group (CET). @372 +* 20 Apr 1988 +S857. Make sure \\{temp_head} is well-formed whenever it can be + printed in a ``runaway'' message: Consider constructions like + |\outer\def\a0{}\a\a| (Silvio Levy). @391 +* 24 Apr 1988 +S858\>618. Avoid conflicting use of the string pool in constructions like + |\def\\#1{}\input a\\\z| (Robert Messer). @260 +* 10 May 1988 +R859. Amend the |\patterns| data structure when $\\{trie_min}=0$ + (PB). @951,953 +* 25 May 1988 +R860. Guarantee that \\{trie_pointer} cannot be out of range. @923 +S861\>618. Avoid additional bugs like \#858 in constructions + like |\input a\romannumeral1|, etc. @464,465,470 +R862\>618. Prevent similar string pool confusion that could occur + during the processing of |**\input\romannumeral6|. @525 +* 19 Jun 1988 +S863\>819. Prevent a negative dividend from rounding upward, + causing a loop (CET). @126 +E864\>819. Adopt a smoother allocation strategy when + memory is nearly gone (CET). @126 +* 20 Jun 1988 +D865\>852. Initialize \\{cur_order}, now that it's being backed up + (Tsunetoshi Hayashi). @439 +* 6 Nov 1988 +S866\>612. Disable \\{fatal_error} in \\{prompt_input}, so that + \\{open_log_file} can use it safely (Tim Morgan). @71 +S867\>836. Force terminal output whenever \\{open_log_file} fails. @535 +* 14 Dec 1988 +P868\>866. Restore \\{fatal_error} in \\{prompt_input}, but don't + let it be unsafe for \\{open_log_file}. @92,534 +* 23 Jan 1989 +D869. Give $q$ a legal value when recovering from ``infinite shrinkage'' + error. @976,1004 +* 17 Feb 1989 +D870\>758. Avoid spurious error message for |\aftergroup\relax\dump| by avoiding + inaccessible |\aftergroup| tokens (FM and Rainer Sch\"opf). @280 +* 20 Mar 1989 +R871. Don't refer to \\{link}(\\{null}) even when it ``can't happen'' + (PB). @791 +* 7 Jun 1989 +S872. Avoid confusion from |$$\begingroup\halign{#\cr}$$| (FM). @1130 +* 20 Jun 1989 +S873. Put fraction digits into dynamic memory, not the global \\{dig} array, + because of constructions like |.5\ifdim.6| (FM). @452 +* 17 Jul 1989 +S874. Prevent embarrassing attempts to report errors before the string + mechanism has been fully initialized, for example when the + command line exceeds the buffer size (WGS). @31 +* 16 Aug 1989 +M875. Allow integer products to be 31 bits long (FM). @105 +* 31 Aug 1989 +C876\>441. Increase the number of tokens shown by \\{token_show} + (J. Lavagnino). @295 +S877. Avoid confusion from |$$\begingroup\eqno$$| (FM). @1140 +# The recent TUG meeting turned out to be an extend-\TeX-for-the-nineties + party! I agreed that some extensions for non-English languages + ought to be made while I still knew how to do them. (In other words, + I broke my firm commitment to keeping \TeX\ completely stable; + but in this case nobody objected.) The following eleven changes + were coded during the month of September. +* 30 Sep 1989 +G878. Install major change allowing general 8-bit code input. @38,352 +G879. Install major change allowing multiple hyphenation tables + (M. Ferguson). @923 +G880. Introduce new parameters |\lefthyphenmin| and |\righthyphenmin|. @923 +G881. Introduce major new ligature capabilities including implicit + boundary characters. @908,1037 +G882. Install new |\inputlineno| feature suggested by MDS. @424 +G883. Install new |\holdinginserts| feature suggested by FM. @1014 +G884. Install new |\badness| feature. @424,664 +G885. Install new |\emergencystretch| feature. @863 +G886. Install new |\errorcontextlines| feature suggested by FM. @311 +S887. Recover from anomaly when hyphenation |char_warning| clobbers + |old_setting|. @863 +P888. Make it easier to change the format extension (Don Hosek). @520,1328 +* 16 Oct 1989 +R889. Avoid range check in null font with |bc=256| (PB). @565 +* 22 Nov 1989 +S890\>856. Prevent \\{save_stack} conflicts in + |{\hbox\expandafter{\csname\endcsname}}| and\kern-3pt\break + similar constructions (WGS). @645,1117 +S891\>858. System-dependent parts of file names must be addressed relatively, + not absolutely (FM and Rainer Sch\"opf). @516,517 +* 3 Dec 1989 +G892\>880. Allow different hyphenmins in the same paragraph (M. Ferguson). @1376 +S893. Distinguish |\par| from characters on |\if| tests. (MVL). @334 +S894\>378. Alignments need to be more robust against malicious + attacks (MVL). @782 +C895. Don't let kerns in discretionaries disappear at breaks (MVL). @869 +Q896\>881. Make the new hyphenation reconstruction procedure less cautious, + so that it doesn't lose hyphens found by the old method. @914 +* 11 Dec 1989 +D897\>879. Make an undumped trie dumpable again (PB). @1325 +* 18 Dec 1989 +G898\>588. Allow access to page totals in |\output| routines + (FM and Chris Rowley). @421 +* 22 Jan 1990 +R899\>611. Recognize more cases of unbalanced |\output| (CET). @1026 +* 29 Jan 1990 +S900\>758. Make |\aftergroup| work properly after |\eqno| (Michael Downes). + @1194 +* 1 Feb 1990 +S901\>878. Fix one more case of \\{end_line_char_inactive} (WGS). @360 +* 22 Feb 1990 +R902. Don't lose the last active node when total demerits are very high (FM). + @836,854 +* 13 Mar 1990 +D903. Doublecheck math fonts after making equation number (MVL). @1194 +D904. Don't forget to rule out charnodes before testing \\{type} (MVL). + @805,1202 +* 23 Mar 1990 +F905\>881. Don't change the font of punctuation preceding a hyphenated word + (Scott C. Allendorf). @903 +I906. Balance the parentheses shown on the terminal during normal runs. @1335 +E907. Optimize |\ifx\p\q| after |\let\p=\q| (MVL). @508 +S908. Treat migration properly in displays (MVL). @1199,1205 +# We're now up to Version 3.0; I sincerely hope all bugs have been found. +* 11 May 1990 +F909\>881. Initialize |\nullfont| ligature parameters (Lance Carnes). @552 +* 22 July 1990 +S910\>579. Treat |\prevgraf| as zero within |\write| (Bogus\l aw Jackowski). + @422 +* 26 July 1990 +S911. Report `|l.1|' when first line of file overflows buffer + (George Russell). @538 +* 5 December 1990 +S912\>878. Translate unprintable characters in font identifiers (WGS). @63 +* 28 December 1990 +R913. Avoid range check when there are 65536 or more pages (Eberhard Mattes). + @642 +* 20 September 1991 +I914\>878. Improve error message for |\mathchar| out of range. @436 +S915\>878. Retain unprintable internal strings in 8-bit form (FM). @59 +S916\>881. Retain right punctuation context for ligature reconstruction + (problem found by Brian Hamilton Kelly). @903 +* 10 January 1992 +S917\>881. Also avoid producing a double kern at boundary (CET). @897 +S918. Disallow |\setbox| where it doesn't work (Robert Hunt). @1241,1270 +S919. Robustify |\mskip| and |\mkern| in presence of negative quad (WGS). + @716,717 +S920\>679. Defend against `|}{|' in |\read| (Michael Downes). @483 +E921\>798. Save string memory if font occurs repeatedly (Bogus\l aw Jackowski). + @1260 +S922\>784. Don't let |\newlinechar| interrupt unprintable expansion (Bernd + Raichle). @59,60 +* 7 February 1992 +D923\>881. Restore |cur_l| properly when boundary character doesn't exist + (Mattes and Raichle). @1036 +* 17 July 1992 +C924\>892. Use current language at beginning of horizontal mode (Rainer + Sch\"opf and CET). @1091,1200 +* 17 December 1992 +R925\>879. Avoid (harmless) range errors (Philip Taylor and CET). @934,960 +* 25 February 1993 +C926\>881. Protect kerns inserted by boundary characters (William Baxter). + @837,866 +S927\>917. Don't let boundary kern disappear after hyphenation. @897 +* 26 June 1993 +R928\>668. Avoid potential future bug (Peter Breitenlohner). @628,637 +* 17 December 1993 +S929\>881. Boundary character representation shouldn't depend on the font + memory size (Berthold Horn). @549,1323 +* 10 March 1994 +R930. Huge font parameter number may exceed array bound (CET). @549 +* 4 September 1994 +F931\>926. Math kerns are explicit (Walter Carlip). @717 +R932. Avoid overflow on huge real-to-integer conversion. @625,634 +* 19 March 1995 +R933. Avoid spurious reference counts in format files (PB). @1335 +* 23 November 1998 +R934. Make sure that TeX is certifiably Y2K-safe. @1328 +* 12 July 1999 +A935\>255. |\xleaders| often drops the final box (Hiroshi Nakashima). @627,636 +* 30 August 2001 +R789. Don't allow a million unbalanced braces followed by |\cr| + outside of any alignment (Ralf Roth). @789 +R790. Don't allow end-template except at end of template (Roth). @325,1131 +* 30 September 2002 +Q791. Improve rounding of glue during output (M. F. Bridgland). @625,634 +\relax +\bye + +Up to a point it is better to let the snags [bugs] be there +than to spend such time in design that there are none +(how many decades would this course take?). +-- A M Turing + Proposals for Development in the Mathematics Division + of an Automatic Computing Engine (ACE) + Report E882, Executive Committee, National Physical Laboratory (NPL) + 1945; reprinted in April 1972 as NPL report Com Sci 57 + page 18 + quoted by Carpenter and Doran in The Computer Journal 20 (1977), 273. + +DRF David Fuchs +HWT Howard Trickey +FY Frank Yellin +LL Leslie Lamport +JS Jim Sterken +ARK Arthur Keller +CET Chris Thompson +FM Frank Mittelbach (added subsequent to publication of paper) +PB Peter Breitenlohner (ditto) +WGS Wayne G. Sullivan (ditto) +MVL Marc van Leeuwen (ditto) +MDS Michael D. Spivak (ditto) |