From 8d8d528d2ad52599f11250cfc567fea4f37f2a8b Mon Sep 17 00:00:00 2001 From: Context Git Mirror Bot Date: Tue, 12 Jan 2016 17:15:07 +0100 Subject: 2016-01-12 16:26:00 --- tex/context/base/mkii/catc-sym.mkii | 187 ++++++++++++++++++++++++++++++++++++ 1 file changed, 187 insertions(+) create mode 100644 tex/context/base/mkii/catc-sym.mkii (limited to 'tex/context/base/mkii/catc-sym.mkii') diff --git a/tex/context/base/mkii/catc-sym.mkii b/tex/context/base/mkii/catc-sym.mkii new file mode 100644 index 000000000..55782f11e --- /dev/null +++ b/tex/context/base/mkii/catc-sym.mkii @@ -0,0 +1,187 @@ +%D \module +%D [ file=catc-sym, +%D version=1997.01.03, % moved code +%D title=\CONTEXT\ Catcode Macros, +%D subtitle=Some Handy Constants, +%D author=Hans Hagen, +%D date=\currentdate, +%D copyright={PRAGMA ADE \& \CONTEXT\ Development Team}] +%C +%C This module is part of the \CONTEXT\ macro||package and is +%C therefore copyrighted by \PRAGMA. See mreadme.pdf for +%C details. + +% we now have loaded syst-* so we have all @@catcode constants + +%D We want to have access to the raw alternatives of the +%D special characters. We use a \type {\xdef} instead of +%D \type {\let} because we need an expandable token in a +%D \type {\write}. + +\bgroup + +\catcode`B=\begingroupcatcode +\catcode`E=\endgroupcatcode +\catcode`.=\escapecatcode + +.catcode `.{ 12 .xdef .letteropenbrace B.string{E +.catcode `.} 12 .xdef .letterclosebrace B.string}E +.catcode `.& 12 .xdef .letterampersand B.string&E +.catcode `.< 12 .xdef .letterless B.string 12 .xdef .lettermore B.string>E +.catcode `.# 12 .xdef .letterhash B.string#E +.catcode `." 12 .xdef .letterdoublequote B.string"E +.catcode `.' 12 .xdef .lettersinglequote B.string'E +.catcode `.$ 12 .xdef .letterdollar B.string$E +.catcode `.% 12 .xdef .letterpercent B.string%E +.catcode `.^ 12 .xdef .letterhat B.string^E +.catcode `._ 12 .xdef .letterunderscore B.string_E +.catcode `.| 12 .xdef .letterbar B.string|E +.catcode `.~ 12 .xdef .lettertilde B.string~E +.catcode `.\ 12 .xdef .letterbackslash B.string\E +.catcode `./ 12 .xdef .letterslash B.string/E +.catcode `.? 12 .xdef .letterquestionmark B.string?E +.catcode `.! 12 .xdef .letterexclamationmark B.string!E +.catcode `.@ 12 .xdef .letterat B.string@E +.catcode `.: 12 .xdef .lettercolon B.string:E + + .global .let .letterescape .letterbackslash + .global .let .letterbgroup .letteropenbrace + .global .let .letteregroup .letterclosebrace + .global .let .letterleftbrace .letteropenbrace + .global .let .letterrightbrace .letterclosebrace + +.egroup + +%D \macros +%D {uncatcodespecials,setnaturalcatcodes,setnormalcatcodes, +%D uncatcodecharacters,uncatcodeallcharacters, +%D uncatcodespacetokens} +%D +%D The following macros are more or less replaced by switching +%D to a catcode table (which we simulate in \MKII) but we keep +%D them for convenience and compatibility. Some old engine code +%D has been removed. + +\def\uncatcodespecials {\setcatcodetable\nilcatcodes \uncatcodespacetokens} +\def\setnaturalcatcodes {\setcatcodetable\nilcatcodes} +\def\setnormalcatcodes {\setcatcodetable\ctxcatcodes} % maybe \texcatcodes +\def\uncatcodecharacters {\setcatcodetable\nilcatcodes} % was fast version, gone now +\def\uncatcodeallcharacters{\setcatcodetable\nilcatcodes} % was slow one, with restore + +\def\uncatcodespacetokens + {\catcode\spaceasciicode \spacecatcode + \catcode\formfeedasciicode \ignorecatcode + \catcode\endoflineasciicode\endoflinecatcode + \catcode\delasciicode \ignorecatcode} + +%D \macros +%D {setverbosecharacter,setverbosecscharacters} +%D +%D Next follows a definition that lets some shortcuts expand to +%D themselves. This macro is meant for \POSTSCRIPT\ and \PDF\ +%D code passed on to the backend. + +\newtoks\everyverbosechacters + +\def\setverbosecscharacter#1% + {\edef#1{\string#1}} + +\def\setverbosecscharacters + {\the\everyverbosechacters} + +\bgroup + + % if used often we can move the code inline + + \catcode\barasciicode \activecatcode + \catcode\tildeasciicode\activecatcode + + \global \everyverbosechacters = + {\setverbosecscharacter |\setverbosecscharacter ~% context specific + \setverbosecscharacter\|\setverbosecscharacter\~% + \setverbosecscharacter\:\setverbosecscharacter\;% + \setverbosecscharacter\+\setverbosecscharacter\-% + \setverbosecscharacter\[\setverbosecscharacter\]% + \setverbosecscharacter\.\setverbosecscharacter\\% + \setverbosecscharacter\)\setverbosecscharacter\(% + \setverbosecscharacter\0\setverbosecscharacter\1% + \setverbosecscharacter\2\setverbosecscharacter\3% + \setverbosecscharacter\4\setverbosecscharacter\5% + \setverbosecscharacter\6\setverbosecscharacter\7% + \setverbosecscharacter\8\setverbosecscharacter\9% + \setverbosecscharacter\n\setverbosecscharacter\s% + \setverbosecscharacter\/} + +\egroup + +%D (Inspired by a discussion on the \CONTEXT\ mailing list) +%D +%D In \TEX\ each character can have one of 16 catcodes. This way the +%D backslash, dollar, ampersand, hash and some more characters get +%D their special meaning. If you want to process tokens under a +%D certain catcode regime, passing arguments can interfere badly. +%D +%D \startbuffer[a] +%D \def\whatever#1{[#1]} +%D \whatever{whatever \type {\whatever{you want}} $or$ not!} +%D \stopbuffer +%D +%D \typebuffer[a] +%D +%D Here we pass an argument to \type {\whatever} but part of that +%D argument is to be processed under a different catcode regime, i.e.\ +%D all characters that need to be typeset verbatim need to get +%D the catcode that makes it a letter. This is what we get when we typeset +%D the text verbatim: +%D +%D \starttyping +%D whatever \type {\whatever{you want}} $or$ not! +%D \stoptyping +%D +%D However, when passed to \type {\whatever} we get: +%D +%D \getbuffer[a] +%D +%D In \ETEX\ one can use \type {\scantokens} to circumvent this problem. +%D +%D \startbuffer[b] +%D \def\rescan#1{\scantokens{#1}} +%D \def\whatever#1{[\rescan{#1}]} +%D \whatever{whatever \type {\whatever{you want}} $or$ not!} +%D \stopbuffer +%D +%D \getbuffer[b] \typebuffer[b] +%D +%D This time the \type {\whatever} call gives: +%D +%D \getbuffer[b] +%D +%D In this example, two spaces have crept in. The first one, after the +%D macro name, is inserted by \TEX\ and cannot be avoided. The last space +%D is inserted by \type {\scantokens}, and is the consequence of the fact +%D that this macro mimics reading from a file. You can avoid the last +%D space by a slightly different definition: +%D +%D \startbuffer[c] +%D \def\rescan#1{\scantokens{#1\ignorespaces}} +%D \def\whatever#1{[\rescan{#1}]} +%D \whatever{whatever \type {\whatever{you want}} $or$ not!} +%D \stopbuffer +%D +%D \typebuffer[c] +%D +%D Unfortunately we still keep the first space, but at least it's better than +%D a failure: +%D +%D \getbuffer[c] + +\long\def\rescan#1{\scantokens{#1\ignorespaces}} +\long\def\rescanwithsetup#1#2{\begingroup\directsetup{#1}\scantokens{#2\ignorespaces}\endgroup} + +\ifx\scantextokens\undefined \else + \long\def\rescan#1{\scantextokens{#1}} + \long\def\rescanwithsetup#1#2{\begingroup\directsetup{#1}\scantextokens{#2}\endgroup} +\fi + +\endinput -- cgit v1.2.3