diff options
Diffstat (limited to 'Master/texmf-dist/doc/latex/loops')
| -rw-r--r-- | Master/texmf-dist/doc/latex/loops/README | 483 |
1 files changed, 483 insertions, 0 deletions
diff --git a/Master/texmf-dist/doc/latex/loops/README b/Master/texmf-dist/doc/latex/loops/README new file mode 100644 index 00000000000..6eaa9719cbf --- /dev/null +++ b/Master/texmf-dist/doc/latex/loops/README @@ -0,0 +1,483 @@ +This is the README file for the 'loops' package. + +*** Location: latex/macros + +AUTHOR + +Ahmed Musa + +VERSION + +Version 1.0, September 2012. + +LICENSE + +Copyright (c) 2012 Ahmed Musa + +This software is author-maintained. Permission is granted to copy, +distribute and/or modify this software under the terms of the +LaTeX Project Public License, version 1.3 or higher. This software +is provided 'as it is', without warranty of any kind, either +expressed or implied, including, but not limited to, the implied +warranties of merchantability and fitness for any particular purpose. + + +SUMMARY + +The 'loops' package provides efficient looping macros for processing +both csv (separated-values) and nsv/tsv (non-separated values) lists. +csv lists having arbitrary parsers, and even active parsers, can +be processed with the tools of this package. + +All our loops can be safely nested. Breaking the inner loop doesn't +affect the continuation of the outer loop. + +The looping macros include: + +\skvrecurse: + + \skvrecurse{<body>}\while<\if...>\fi + + A variant of D.E. Knuth's \loop macro. + + \@tempcnta\z@ + \skvrecurse{ + \advance\@tempcnta\@ne + \@tempcntb\z@ + \skvrecurse + \advance\@tempcntb\@ne + \typeout{Doing \the\@tempcnta,\the\@tempcntb} + \while + \ifnum\@tempcntb<3\relax + \fi + } + \while + \ifnum\@tempcnta<4\relax + \fi + + +\carlisleloop: + + \carlisleloop<id>{<body>}<\if...>\repeat<id> + + A nesting version of D.E. Knuth's \loop macro, + adapted from the original macros of David Carlisle. + + \skvnewcounts{rowcnt,colcnt,maxrow,maxcol} + \maxrow4 \maxcol3\relax + \def\entries{} + \let\xp\skvexpandonce + \def\generate{% + \advance\colcnt\@ne + \edef\entries{\xp\entries\the\numexpr\rowcnt*\colcnt\relax}% + \ifnum\colcnt<\numexpr\maxcol+1\relax\relax + \edef\entries{\xp\entries\noexpand&}% + } + \def\generateentries{% + \carlisleloop\a + \advance\rowcnt\@ne\colcnt\z@ + \carlisleloop\b + \generate + \repeat\b + \ifnum\rowcnt<\numexpr\maxrow+1\relax\relax + \edef\entries{\xp\entries\noexpand\cr}% + \repeat\a + \edef\entries{\xp\entries\noexpand\crcr}% + } + \begin{document} + \generateentries + $$\vbox{\halign{&\ \hfil#\hfil\strut\cr\entries}}$$ + \end{document} + + +\akterloop: + + \akterloop{<body>}<\if...>\repeat + + A generalized and naturally nesting version of D.E. Knuth's + \loop macro. No nesting brace is required, unlike in \skvrecurse. + No <id> is required, unlike in \carlisleloop. + + \def\generateentries{% + \akterloop + \advance\rowcnt\@ne\colcnt\z@ + \akterloop + \generate + \repeat + \ifnum\rowcnt<\numexpr\maxrow+1\relax\relax + \edef\entries{\xp\entries\noexpand\cr}% + \repeat + \edef\entries{\xp\entries\noexpand\crcr}% + } + \begin{document} + \generateentries + $$\vbox{\halign{&\ \hfil#\hfil\strut\cr\entries}}$$ + \end{document} + + +\skvtfor: + + \skvtfor<holder.cmd>{<list>}\do{<callback>} + \skvtfor*<holder.cmd>{<listcmd>}\do{<callback>} + + A variant of LaTeX kernel's \@tfor that has a different + approach to breaking the loop prematurely. + + \skvnewregister\count\nr + \skvtfor\x:=a \ifx {\def\x#1{#1}} \fi\do{% + \nr\z@ + \skvtfor\y:=12345\do{% + \typeout{Doing: \detokenize\expandafter{\x}--\y}% + \advance\nr\@ne + \ifnum\nr>\tw@\skvbreakloop\fi + }% + } + + +\ayeloop: + + \ayeloop{<list>}\do{<1.parameter.callback>} + \ayeloop*{<listcmd>}\do{<1.parameter.callback>} + + A variant of \skvtfor that uses parameter characters + directly, instead of a holder macro. + + \ayeloop abcd\do{% + \def\nr{0}% + \ayeloop 12345\do{% + \typeout{Doing #1--##1}% + \skvpushnumber\nr + \ifnum\nr>3\relax\skvbreakloop\fi + }% + } + + +\sifakaloop: + + \sifakaloop{<list>}{<1.parameter.callback>} + \sifakaloop*{<listcmd>}{<1.parameter.callback>} + + \sifakaloop is as \ayeloop but will first normalize the list + using \skvtsvnormalize before parsing. Unlike all the + other nsv/tsv loops, it preserves outer braces in the + arguments. Hence, it is costlier. You can insert \listbreaker + as a token in <list> or <listcmd> to terminate the list prematurely. + + +\skvfor: + + \skvfor{<list>}<1.parameter.callback.macro> + + \skvfor is an expandable comma loop. The list is not + normalized prior to parsing, and it is not possible to + terminate the loop prematurely (ie, before exhausting + the list). + + \skvnewregister\count\nr\nr=\tw@ + \def\do#1{% + \let\noexpand#1% + \expandafter\noexpand\csname\skvremovescape{#1}@% + \romannumeral\nr\endcsname + } + \edef\x{\skvfor{\cmda,\cmdb}\do} + \show\x -> \let\cmda\cmda@ii \let\cmdb\cmdb@ii + + +\skvcommaloop, \skvecommaloop, \skvcommaparse, \skvkvparse: + + \skvcommaloop{<list>}<holder-cmd>{<callback>} + \skvcommaloop*{<listcmd>}<holder-cmd>{<callback>} + + All these have the same syntax. \skvecommaloop is as + \skvcommaloop but will execute <callback> once when <list> + is empty. This is needed for processing empty key families. + + \skvcommaparse is as \skvcommaloop but will first normalize + <list> using \skvcsvnormalize. \skvkvparse is as \skvcommaloop + but will first normalize <list> using \skvkvnormalize. + \skvkvparse is meant for processing key-value lists. + + +\skvdolist and \skvparselist: + + \skvparselist{<parser>}{<list>}<holdercmd>{<callback>} + \skvparselist*{<parser>}{<listcmd>}<holdercmd>{<callback>} + + These can process lists with arbitrary parsers/list + separators.The only difference between \skvdolist and + \skvparselist is that \skvparselist will first normalize + the list before parsing. + + +\cicadaloop: + + \cicadaloop[<parser>]{<list>}<\if...>\fi{<callback>} + \cicadaloop*[<parser>]{<listcmd>}<\if...>\fi{<callback>} + + \cicadaloop will terminate prematurely on the current depth + whenever the condition specified by <\if...> is true. + <callback> is the regular code, to be executed + for every item of the list before the loop is terminated. + + Some internal macros are accessible by the user: \iflastcicada, + \currentcicada, \nextcicada, \lastcicada, \cicadacount. + \cicadacount is depth-dependent. + + You can insert \listbreaker as an item in <list> or <listcmd> + to terminate the list prematurely. \listpauser isn't recognized by + \cicadaloop. + + \let\romn\romannumeral + \@tempcnta\z@ + \def\blist{{X};{Y};Z;\fi} + \def\stack{} + \cicadaloop{{a},{b},c,\if}\if01\fi{% + \advance\@tempcnta\@ne + \@tempcntb\z@ + \@tempswafalse + \cicadaloop*[;]\blist\if@tempswa\fi{% + \advance\@tempcntb\@ne + \typeout{Doing \romn\@tempcnta,\romn\@tempcntb: + \detokenize{#1,##1}}% + \edef\stack{% + \unexpanded\expandafter{\stack}\noexpand\do + {\romn\@tempcnta,\romn\@tempcntb}{\unexpanded{#1;##1}}% + }% + \ifnum\@tempcntb>\@ne + \@tempswatrue + \skvcsedef{cmd@\romn\cicadaloopdepth}{\lastcicada,\cicadacount}% + \fi + }% + } + \show\stack + + +\newforeach: + + \newforeach[<options>]<holder.macros>{<optional.'in'>} + {<list.or.listcmd>}{<optional.'do'>}{<callback>} + \newforeach<holder.macros>[<options>]{<optional.'in'>} + {<list.or.listcmd>}{<optional.'do'>}{<callback>} + + The star (*) form of \newforeach is equivalent to declaring + the option 'list is a macro' in <options>. + + \newforeach is a more versatile and robust version of the popular + \foreach macro of the PGF bundle. The macro accepts arbitrary list + parsers and sub-parsers, including active list separators. + When needed, parameters corresponding to the holder macros can + be used directly in the callback. \newforeach does everything + that PGF's \foreach does. It doesn't automatically scope + calculations as \foreach does. Automatically creating local + groups for computations has been a problem for some users + of \foreach. Instead, \newforeach uses stacks to save and + restore the values of holder macros and some other internal + parameters/quantities. + + There is a long list of options, ie, keys in <options>, + available for \newforeach and \foxloop. Also, there are many + internal macros that can be accessed by the user. A few of them + are \interruptforeach, \foreachcurrentitem, \foreachnextitem, + \foreachitemcount, \foreachprevitem, \prependtobeginforeach, + \appendtobeginforeach, \prependtoendforeach, \appendtoendforeach, + \ifforeachlastitem, \foreachnestdepth, \foreachlistremainder. + \foreachitemcount counts the items as the loop progresses. + It is depth dependent, ie, it can be called to access the + number of items processed on each depth of nesting of + \newforeach. On any depth, the user can say, eg, + + \ifnum\foreachitemcount>10\relax\interruptforeach\fi + + or + + \ifnum\foreachitemcount>10\relax\interruptloop\fi + + You can insert \listbreaker as an item in <list> or <listcmd> + to terminate the list prematurely. \listpauser will pause + the processing for user action. + + Maybe you fancy the following syntactic sugar, which PGF's + \foreach can't presently process: + + \begingroup + \catcode`\,=13 + \gdef\alist{1,2,...,5,7,8,...,12} + \endgroup + \parindent-20pt + \begin{tikzpicture} + \draw[step=.5cm,blue!65,very thin] (0,0) grid (13,6); + \newforeach* \x [ + count in=\xc all \x satisfying \ifnum\x>5\fi + ] in \alist { + \newforeach [ + parser={;}, + subparser=:, + evaluate=\y as \ye using \numexpr\y*10 + ] + \y:\z in {1:red; 2:green; 3:blue; 4:brown; 5:purple} do { + \draw [fill=\z\ifnum\x>5!\ye\fi] (\x,\y) +(-.5,-.5) + rectangle ++(.5,.5); + \draw (\x,\y) node {\x,\y}; + } + } + \global\let\xc\xc + \end{tikzpicture} + \show\xc + + % Example credit: Tom Bombadil + \usetikzlibrary{arrows} + \parindent-40pt + \begin{tikzpicture} + % You may fix \pgfmathsetseed to get a constant output: + % \pgfmathsetseed{42} + \newforeach \y [count=\yc] in {-0.5,-1,...,-2.5} {% + \node[right] at (15.2,\y+0.1) {\scriptsize Subject \yc}; + \newforeach \x in {1,...,300}{% + \pgfmathtruncatemacro{\drawbool}{rand-0.7 > 0 ? 1 : 0}% + \ifnum\drawbool=1\relax + \fill (\x/20,\y) rectangle (\x/20+0.05,\y+0.3); + \fi + }% + }% + \draw[-stealth] (0,0) -- (15.5,0); + \node[right] at (15.5,0.2) {t in ms}; + \newforeach \x [ + pgf evaluate=\x as \xv using int(20*\x) + ] in {0,...,15} {% + \draw (\x,-0.05) -- (\x,0.05) node[above] {\xv}; + } + \end{tikzpicture} + + Here, it is possible to use #1, ##1, ##2 in the callback to + refer to \x, y, \z, respectively. This relieves the user of the + need to manually expand the holder macros \x,\y,\z in the callbacks, + as I have seen some TikZ users do. + + \newforeach found a bug in PGF's \foreach, as reported at + <http://tex.stackexchange.com/questions/72707/an-unexpected- + outcome-from-pgfs-foreach>. However, \newforeach itself + can't be said to be bug free. + + +\foxloop: + + \foxloop[<options>]{<list>}{<parametered.callback>} + \foxloop*[<options>]{<listcmd>}{<parametered.callback>} + + \foxloop does everything that \newforeach does, but, in addition, + it can process nsv/tsv (non-separated lists). It can auto-complete + ellipsis lists (ie, lists with '...'), but this feature is + available only for csv lists and not for nsv lists. + + 1. One important characteristic of \foxloop is that it doesn't use + holder macros (eg, \x/\y), but instead it uses parameter + characters directly. So it doesn't accept/expect holder macros. + 2. That means that if the argument isn't simple (ie, #1), then it + has to be specified as the value of the key/option 'arg' (eg, + arg=#1/#2). + 3. Note that \foxloop doesn't expect any optional 'in' or 'do'. + 4. Unlike \newforeach, \foxloop doesn't recognize the semicolon + (;) as a callback terminator. In fact, the callback for \foxloop + should ideally be always enclosed in balanced braces. PGF + often uses the semicolon as the callback terminator. \newforeach + supports that feature. + + The following macros are available to the user: + + \breakfoxloop, \interruptloop, \foxloopdepth, \foxcount, + \previousfox, \currentfox, \nextfox, \iflastfox, + \foxlistremainder, \prependtobeginfoxloop, \appendtobeginfoxloop, + \prependtoendfoxloop, \appendtoendfoxloop. + + + Examples: + + \foxloop [ + remember=#1 as \x initially A + ] {B,...,H} {% + $\overrightarrow{\x#1}$\iflastfox.\else,\space\fi + } + + This is equivalent to: + + \foxloop [ + list type=tsv, + remember=#1 as \x initially A + ] {BCDEFGH} {% + $\overrightarrow{\x#1}$\iflastfox.\else,\space\fi + } + + \usepackage{multicol} + \begin{document} + \begin{multicols}{2} + \foxloop [count=\nchar] {a,...,f} { + \foxloop [ + evaluate=##1 as \xe using \numexpr##1*20, + evaluate=##1 as \hx using \pgfmathparse{##1 mm*5}, + evaluate=##1 as \vx using \pgfmathparse{##1 mm*1.5}, + count in= \ci all ##1 satisfying \ifnum##1<4\fi initially 2, + count in= \di all ##1 satisfying \ifnum##1>2\fi, + ] {1,...,6} { + \endgraf + Doing: #1, ##1, \nchar, \ci, \di + \endgraf + \ifnum\nchar>3\relax + \vskip-\vx pt\relax + \fi + \hskip\hx pt\relax + \tikz[rounded corners,ultra thick]{ + \shade[ball color=red!\xe!blue] (0,0) circle (.25cm); + \node[white,font=\large] (0,0) {#1}; + }% + }% + } + \end{multicols} + \end{document} + + + % Example credit: Heiko Oberdiek + \makeatletter + \let\do\newdimen\do\DimWD\do\DimHT\do\DimDP + \newcommand*{\DimBox}[1]{% + \begingroup + \sbox0{\makebox[\DimWD]{#1}}% + \ht0=\DimHT\dp0=\DimDP\usebox\z@ + \endgroup + } + \newcommand*{\DimMeasure}[3]{% + \node at (0,0) {% + \let\do\global + \do\DimWD\z@\do\DimHT\z@\do\DimDP\z@ + \foxloop* [arg=##1/##2,parser={#1}] #2 {% + \sbox0{#3}% + \ifdim\wd0>\DimWD\global\DimWD=\wd0\fi + \ifdim\ht0>\DimHT\global\DimHT=\ht0\fi + \ifdim\dp0>\DimDP\global\DimDP=\dp0\fi + }% + };% + } + \makeatother + \begin{document} + \def\yellowlist{a/-1,-2;b/1,-2;c/2,-1;d/2,1;e/1,2;f/-1,2;g/-2,1;h/-2,-1} + \def\bluelist{a/b,b/c,c/d,d/e,e/f,f/g,g/h,h/a} + \begin{tikzpicture}[scale=1.2,auto=left,every node/.style={circle,thick}] + \DimMeasure{;}{\yellowlist}{#1} + \foxloop* [arg=#1/#2,parser={;},count=\xc] \yellowlist { + \node (#1) at (#2) [fill=blue!20,draw=yellow] {\DimBox{#1}}; + } + \DimMeasure{,}{\bluelist}{#1--#2} + \foxloop* [arg=#1/#2] \bluelist { + \draw [->] (#1) -- (#2) + node [midway,fill=red!20,draw=blue]{\DimBox{#1--#2}}; + } + \end{tikzpicture} + \end{document} + + +NOTE + +Non-LaTeX users can use the \newforeach macro (and some other +looping macros) by loading the file skeyval-for.tex. + + +% End of readme file of loops.sty
\ No newline at end of file |