diff options
Diffstat (limited to 'macros/optex/base/prefixed.opm')
-rw-r--r-- | macros/optex/base/prefixed.opm | 153 |
1 files changed, 84 insertions, 69 deletions
diff --git a/macros/optex/base/prefixed.opm b/macros/optex/base/prefixed.opm index a599e0ec85..023f3bc4de 100644 --- a/macros/optex/base/prefixed.opm +++ b/macros/optex/base/prefixed.opm @@ -152,44 +152,70 @@ \_endcode %---------------------------------------------------- -\sec[prefixed] Concept of namespaces of control sequences +\sec[basic-code] Basic principles of \OpTeX/ sources -\secc Prefixing internal control sequences +\secc[namespaces] Concept of namespaces of control sequences -All control sequences used in \OpTeX/ are used and defined with `_` prefix. -The user can be sure that when he/she does `\def\foo` then neither internal macros of -\OpTeX/ nor \TeX/ primitives will be damaged. For example -`\def\if{...}` will not damage macros because \OpTeX/'s macros -are using `\_if` instead of `\if`. +\OpTeX/ sets the category code of the \"`_`" character to 11 (letter) +and it is never changed.\fnote +{This is only singular exception form category codes given by plain \TeX.} +So, we can always construct multiletter control sequence names from letters +`A`--`Z`, `a`--`z`, and `_`. The \"letter `_`" works in math mode as a subscript +constructor because it is set as math active character (see section~\ref[math-macros]). -All \TeX/ primitives are initialized with two representative control -sequences: `\word` and `\_word`, for example `\hbox` and `\_hbox`. -The first alternative is reserved for users or such control sequences -can be re-defined by a user. - -\OpTeX/ sets the character `_` as letter, so it can be used in -control sequences. When a control sequence begins with this character -then it means that it is a primitive or it is used in \OpTeX/ macros as -internal. User can redefine such prefixed control sequence only -if he/she explicitly knows what happens. - -We never change catcode of `_`, so internal macros can be -redefined by user without problems if it is desired. We don't need -something like `\makeatletter` from \LaTeX/. - -\OpTeX/ defines all new macros as prefixed. For public usage of such macros, -we need to set their non-prefixed versions. This is done by +We distinguish following namespaces for multiletter control sequences: +\begitems +* Only alphabetical names are in the {\em public namespace}. They are intended + for end users when creating a document. Sometimes it is called {\em user + namespace} too. For example `\hbox`, `\fontfam`, `\MyMacro`. +* Only alphabetical lowercase names prefixed by single \"`_`" are in the + {\em private namespace}. It is used in \OpTeX/ internal macros. + For example `\_hbox`, `\_fontsel`. +* Names in the form `\_<pkg>_<name>` are in the {\em package namespace}, + see section~\ref[pkg-namespace]. For example `\_qr_size`, `\_math_alist`. +* Names starting with two \"`_`" are in the {\em reserved namespace}. They can be + used for internal control sequences in font family files or in similar cases. +* Other names which include \"`_`" but not as the first character can be used + too, but with care, see the end of this section. +\enditems +All \TeX/ primitives are initialized with two control sequences with the +same meaning: {\em prefixed} control sequence +(in private namespace, for example `\_hbox`) +and {\em unprefixed} control sequence (in public namespace, for example `\hbox`). +All \OpTeX/ macros intended for end users are initialized in these two forms +too, for example `\_ref` and `\ref`. + +Users can declare any control sequences in the public namespace without worrying +that \OpTeX/ behavior is changed. This is because \OpTeX/ uses exclusively +prefixed control sequences in its macros. For example, a user can declare +`\def\fi{finito}` and nothing bad happens, if the user doesn't use `\fi` in +its original primitive meaning. You don't have to know all \TeX/ primitives +and \OpTeX/ macros, you can declare control sequences for your use in the +public namespace without limitations and nothing bad will happen. + +You can use control sequences from private or package namespace in +a \"read-only manner" without changing \OpTeX/ behavior too. +On the other hand, if you re-define a control sequence in the private name +space, the \OpTeX/ behavior can be changed. You can do it +but we suppose that you know what you are doing and what \OpTeX/ +behavior is changed. + +All multiletter control sequences declared by \OpTeX/ are defined in the private +namespace first (`\_def\_macro{...}`). If the declared control sequences are +intended for end users too then they are exported to the public namespace +after that. It is done by the \^`\public` macro: \begtt \catcode`\<=13 \public <list of control sequences> ; \endtt - For example \^`\public`` \foo \bar ;` does `\let\foo=\_foo`, `\let\bar=\_bar`. -At the end of each code segment in \OpTeX/, the `\_public` macro is used. You -can see which macros are defined for public usage in that code segment. +There is an exception of the above mentioned principle. Control sequences +which are alternatives to math characters (`\alpha`, `\forall`, `\subset` etc.) +are declared only in public name space if they are not used in any internal +\OpTeX/ macros. -The macro \^`\private` does the reverse job of `\public` with the same syntax. +The macro \^`\private` does the reverse job of \^`\public` with the same syntax. For example `\private \foo \bar ;` does `\let\_foo=\foo`, `\let\_bar=\bar`. This should be used when an unprefixed variant of a control sequence is declared already but we need the prefixed variant too. @@ -199,45 +225,33 @@ In this documentation: if both variants of a control sequence are declared the unprefixed variant. The code typically defines the prefixed variant and then the \^`\public` (or `\_public`) macro is used. -\secc[user-ns] Namespace of control sequences for users - -Users can (re)define or (re)declare any control sequence with a name without any `_`. -This does not make any problem in internal \OpTeX/ macros.\fnote -{The token `\par` is in user name space too from \OpTeX/ 1.04+ and -Lua\TeX/ 1.14, see also the end of section~\ref[others].} - -User can define or declare control sequences with `_` character, for -example `\my_control_sequence`, but with the following exceptions: - -\begitems -* Control sequences which begin with `_` are reserved for \TeX/ primitives, - \OpTeX/ internal macros and packages internal macros. -* Multiletter control sequences in the form - `\<word>_` or `\<word>_<one-letter>`, where - <word> is a sequence of letters, are inaccessible, because they - are interpreted as `\<word>` followed by `_` or as `\<word>` followed by - `_<one-letter>`. This is important for writing math, for example: -\begtt \adef-{_} - \int-a^b ... is interpreted as \int _a^b - \max-M ... is interpreted as \max _M - \alpha-{ij} ... is interpreted as \alpha _{ij} -\endtt - This feature is implemented using Lua code at input processor level, see - the section~\ref[math-macros] for more details. You can deactivate this feature by - \^`\mathsboff`. After this, you can still write - `$`$\int$`_a^b$` (Unicode) or `$\int _a^b$` % $∫_a^b$ (Unicode) or $\int _a^b$ - without problems but `\int``_a^b` yields to undefined control sequence - `\int``_a`. You can activate this feature again by \^`\mathsbon`. The - effect will take shape from next line read from input file. -* Control sequences in the form `\_<pkg>_<word>` is intended for package - writers as internal macros for a package with `<pkg>` identifier, - see section~\ref[pkg-namespace]. -\enditems - The single-letter control sequences like `\%`, `\$`, `\^` etc. are not used in internal macros. Users can redefine them, but (of course) some classical features can be lost (printing percent character by `\%` for example). +It is very tempting to use control sequence names with `_` in order to +distinguish more words in the sequence name. If the first character isn't +`_` then such a name is outside private and package namespaces, so they can +be used for various purposes. For example `\my_control_sequence`. But there +is an exception: control sequences in the form `\<word>_` or `\<word>_<one-letter>`, +where <word> is a sequence of letters, are inaccessible, because they +are interpreted as `\<word>` followed by `_` or as `\<word>` followed by +`_<one-letter>`. This feature is activated because we want to write math +formulae as in plain \TeX, for example: +\begtt + \int_a^b ... is interpreted as \int _a^b + \max_M ... is interpreted as \max _M + \alpha_{ij} ... is interpreted as \alpha _{ij} +\endtt +It is implemented using Lua code at input processor level, see +the section~\ref[math-macros] for more details. You can deactivate this feature by +\^`\mathsboff`. After this, you can still write +`$`$\int$`_a^b$` (Unicode) or `$\int _a^b$` % $∫_a^b$ (Unicode) or $\int _a^b$ +without problems but `\int``_a^b` yields to undefined control sequence +`\int``_a`. You can activate this feature again by \^`\mathsbon`. The +effect will take shape from next line read from input file. + + \secc Macro files syntax Segments of \OpTeX/ macros or external macro packages @@ -272,7 +286,7 @@ put macros for creating your documentation between first pair of \^`\_doc` ... \^`\_cod` used after \^`\_endcode`. These macros should \^`\load[doc]` and must be finished by \^`\bye`. Then you have code+documentation together in a single file and -user can generate the documentation of our package by +user can generate the documentation of your package by \^`\docgen` used at command line: \begtt optex -jobname pkgname-doc '\docgen pkgname' @@ -307,10 +321,10 @@ does `\let\foo = \_<pkg>_foo` for each given sequence when \^`\_namespace{<pkg>}` is declared. Moreover, it prints a warning if `\foo` is defined already. The \^`\_nsprivate` macro does reverse operation to it without warnings. Example: you can define `\def\.macro{...}` and then -set it to the user name space by `\_nspublic \macro;`. +set it to the public namespace by `\_nspublic \macro;`. It could happen that a package writer needs to declare a control sequence -(say `\foo`) directly without setting it in `\_<pkg>_foo` name space +(say `\foo`) directly without setting it in `\_<pkg>_foo` namespace followed by using \^`\_nspublic`. The \^`\newpublic` prefix should be used in this case, for example `\_newpublic\_def\foo` or `\_newpublic\_chardef\foo` or `\_newpublic{\_long\_def}\foo`. The \^`\newpublic``<do>\<sequence>` prints @@ -338,9 +352,9 @@ If you are writing a macro file that is intended to be published for \OpTeX/, then you are greatly welcome. You should follow these rules: \begitems -* Don't use control sequences from the user namespace in the macro +* Don't use control sequences from the public namespace in the macro bodies if there is no explicit and documented reason to do this. -* Don't declare control sequences in the user namespace if there are no +* Don't declare control sequences in the public namespace if there are no explicit and documented reasons to do this. * Use control sequences from \OpTeX/ and primitive namespace in read-only mode, if there is not an explicit and documented reason to @@ -368,11 +382,12 @@ used directly in \OpTeX/ and from other published macros. This extension `.opm` has precedence before `.tex` when the \^`\load` macro is used. -The `qrcode.opm` is the first example of how an external macro file for \OpTeX/ +The `math.opm` is a good example of how an external macro file for \OpTeX/ can look like. \endinput +2023-01-30 doc. about namespaces rewritten 2022-11-25 \_resetnamespace: moved \gdef\_namesp:#1 {} to \_namespace 2022-11-24 \newpublic introduced, \_checkexists with only two parameters. 2022-11-22 \currfile introduced and used in \_codedecl |