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author | Karl Berry <karl@freefriends.org> | 2012-03-31 22:29:04 +0000 |
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committer | Karl Berry <karl@freefriends.org> | 2012-03-31 22:29:04 +0000 |
commit | 3687879dd2dab0c4f3374c2d800ef35789902105 (patch) | |
tree | 6d33c7f8129ef28e9435fca055ff25a14e0a9c9e /Master/texmf-dist/tex/latex/ifthenx/ifthenx.sty | |
parent | 9c01b63974296c5795e3a8b63460ff6a46bf3b4d (diff) |
new latex package ifthenx (31mar12)
git-svn-id: svn://tug.org/texlive/trunk@25801 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Master/texmf-dist/tex/latex/ifthenx/ifthenx.sty')
-rw-r--r-- | Master/texmf-dist/tex/latex/ifthenx/ifthenx.sty | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/Master/texmf-dist/tex/latex/ifthenx/ifthenx.sty b/Master/texmf-dist/tex/latex/ifthenx/ifthenx.sty new file mode 100644 index 00000000000..3c699818985 --- /dev/null +++ b/Master/texmf-dist/tex/latex/ifthenx/ifthenx.sty @@ -0,0 +1,268 @@ +% $Id: ifthenx.sty 784 2012-03-31 12:00:47Z Geoffrey $ +% +% ifthenx.sty Copyright (C) 2012 Geoffrey Jones 2012/03/31 (v0.1) +% <geoffrey stop jones snailshell uqconnect stop edu stop au> +% +% Package ifthenx.sty -- this little package extends David Carlisle's +% ifthen package, adding a few extra tests. These include: +% \isinteger +% \ispositiveinteger +% \isrealnumber (synonym: \isnumber) +% \ispositiverealnumber (synonym: \ispositivenumber) +% \classloaded +% \packageloaded +% \fileexists +% +% Example: +% \ifthenelse{\ispositiveinteger{\foo}\AND\fileexists{\foo.log}} +% { commands to execute if true } +% { commands to execute if false } +% +% The production rules for numbers are quite straightforward: +% \ispositiveinteger (string of one or more digits) +% \isinteger (ditto, with optional leading minus sign) +% \isrealnumber (ditto, with optional decimal point) +% \ispositiverealnumber (ditto, with no leading minus sign) +% +% Note that well-formed numbers are considered negative if they +% possess a leading minus sign. Accordingly, while 0, 0.0, -0 and +% -0.0 are all well-formed numbers, only 0 and 0.0 test positive. +% Consider this a feature. +% +% Motivation: +% While nowadays the ifthen package is sometimes deprecated (e.g., see the +% March 2011 stackexchange.com conversation on this topic), it has several +% useful attributes that make it attractive in certain situations. +% Setting aside its downsides (particularly, the care needed when using it +% inside fragile contexts), positives include: +% 1. it provides a simple mechanism for assembling complex logical +% expressions, i.e., those employing \AND, \OR, \NOT and \( ... \) +% 2. its syntax, while always subject to preference, may be somewhat +% easier for LaTeX novices to read, write and understand. (To my +% eye, it presents a more approachable and certainly more uniform +% grammar than etoolbox's syntax. E.g., compare +% \ifboolexpr{ test {\ifnumcomp{\value{mycounter}}{>}{3}}}... +% with +% \ifthenelse{\value{mycounter} > 3}... +% ) +% 3. string expansion semantics (cf., etoolbox that does not) +% 4. it is relatively lightweight compared to, say, the might of etoolbox +% (although note that we use etoolbox's \patchcmd if already loaded). +% +% Required Packages: +% ifthen.sty (that's all) +% +% However, note that ifthenx uses \patchcmd if etoolbox.sty is already +% loaded. +% +% Related Packages: +% xifthen.sty provides an alternative set of ifthen package extension +% tests, several of which are based around capabilities drawn from +% the calc package. +% +% xifthen and ifthenx are compatible, but only if xifthen is loaded +% before ifthenx (xifthen doesn't patch \ifthenelse but rewrites its +% own modified version instead). If loaded in the recommended order, +% users can ``mix and match'' the tests. +% For example: +% \newcommand\foo{-4} +% \ifthenelse{\NOT\isundefined{\foo} % native ifthen pkg cmd +% \AND\isnamedefined{foo} % xifthen pkg command +% \AND\isnumber{\foo}}{true}{false} % ifthenx pkg command +% evaluates true. +% +% Version: v0.1 *** prerelease *** +% The author would welcome bug reports, comments, suggestions, +% extensions and so forth at this early stage. +% +% Acknowledgements: +% Gracious thanks David Carlisle for the ifthen package and for +% teaching me a new technique for run-time patching macro code. +% +% This work may be distributed and/or modified under the conditions of the +% LaTeX Project Public License, either version 1.3 of this license or (at +% your option) any later version. The latest version of this license is in +% http://www.latex-project.org/lppl.txt and version 1.3 or later is part of +% all distributions of LaTeX version 2005/12/01 or later. +% +% This work has the LPPL maintenance status `maintained'. +% +% The Original Author of this work is Geoffrey Jones. +% The Current Maintainer of this work is Geoffrey Jones. +% ========================================================================== +\NeedsTeXFormat{LaTeX2e}[1994/12/01] + +\ProvidesPackage{ifthenx} + [2012/03/31 (v0.1) ifthen package extensions (GJ)] + +\RequirePackage{ifthen} + +\def\itx@patchpayload{% + \let\isinteger\itx@isinteger + \let\ispositiveinteger\itx@ispositiveinteger + \let\isrealnumber\itx@isrealnumber% <-- synonyms (a) + \let\isnumber\itx@isrealnumber% <-- synonyms (a) + \let\ispositiverealnumber\itx@ispositiverealnumber% <-- synonyms (b) + \let\ispositivenumber\itx@ispositiverealnumber% <-- synonyms (b) + \let\classloaded\itx@classloaded + \let\packageloaded\itx@packageloaded + \let\fileexists\itx@fileexists +} + +\newif\ifitx@patched +\itx@patchedfalse + +\@ifpackageloaded{etoolbox}{ + % compile-time patch + \patchcmd{\ifthenelse} + {\TE@undef}{\TE@undef\itx@patchpayload} + {\itx@patchedtrue}{} +}{} + +\ifitx@patched\else + % run-time patch + \let\itx@ifthenelse\ifthenelse + \long\def\ifthenelse{\expandafter\itx@@patch\itx@ifthenelse} + \def\itx@@patch#1\TE@undef{#1\TE@undef\itx@patchpayload} + \itx@patchedtrue % quite unnecessary but at least complete +\fi + +% Pattern: all the tests that follow share a similar structure. +% Each entry command sets up conditions then executes a helper +% macro. The helper writes `!' or `?' to a temporary macro, +% respectively to signify test success/true or failure/false. +% This is then expanded and responded to by the mainline command. + +%------------------------------------------------------------------ +% \ifthenelse{\packageloaded{<pkgname>}}{<true part>}{<false part>} +% \ifthenelse{\classloaded{<clsname>}}{<true part>}{<false part>} +%------------------------------------------------------------------ +\def\itx@packageloaded#1#2{% + \TE@neg\TE@throw\noexpand\itx@@packageloaded#1\noexpand\@nil% + \noexpand\if!\@tempa#2} + +\def\itx@@packageloaded#1\@nil{% + \def\@tempa{\if\csname ver@#1.sty\endcsname\relax!\else?\fi}} + +\def\itx@classloaded#1#2{% + \TE@neg\TE@throw\noexpand\itx@@classloaded#1\noexpand\@nil% + \noexpand\if!\@tempa#2} + +\def\itx@@classloaded#1\@nil{% + \def\@tempa{\if\csname ver@#1.cls\endcsname\relax!\else?\fi}} + +%------------------------------------------------------------------ +% \ifthenelse{\fileexists{<file.ext>}}{<true part>}{<false part>} +% +% Normal TeX file search conventions apply, e.g., if file `x.tex' +% exists in the TEXMF file structure or a local path, then +% \ifthenelse{\fileexists{x}}{<true part>}{<false part>} +% will branch to the <true part> path. +% +% \input@path will be searched if the file isn't found in the +% installation TEXMF tree. This can be configured; for example, +% \newcommand*\input@path{{C:/Temp/}{C:/tmp/}} +% Note that each search path must reside within its own group, +% and that each must end with a file path separator '/'. +% +% Also note that this test trims leading (but not trailing) space +% characters from its argument before producing its result. Like +% LateX's native \IfFileExists, this test returns false if passed +% an empty (zero length) filename and, rather absurdly, true +% if the filename expands to \relax. +% +% While our \filexists test (mostly) follows \IfFileExists semantics, +% we resist the urge to emulate the following rather rare and thus +% far unreported bug... +% +% LaTeX2e \IfFileExists bug. Under the following conditions, +% 1. \input@path has been defined, and +% 2. filename includes one or more leading spaces, and +% 3. file does not exist in TEXMF or in \input@path +% then, once for every path specified in \input@path, +% \IfFileExists places filename on the token stream. +% +% Example: +% \newcommand\input@path{{C:/Temp/}{D:/tmp/}} +% \IfFileExists{ xx}{yes}{no} +% produces: +% xx xx no +%------------------------------------------------------------------ +\def\itx@fileexists#1#2{% + \TE@throw\openin\@inputcheck=#1 % local endgroup implicitly closes the file + \noexpand\itx@@fileexists#1\noexpand\@nil% + \noexpand\@tempa\noexpand\if!\@tempb#2} + +\def\itx@@fileexists#1\@nil{% + \def\@tempa{% + \edef\@tempc{% zap leading spaces in #1 + \detokenize\expandafter{\romannumeral-`X\expandafter\noexpand#1}}% + \if\relax\@tempc\relax% catch empty #1 + \def\@tempb{?}% + \else + \ifeof\@inputcheck% + \ifx\input@path\@undefined% + \def\@tempb{?}% + \else% + \@iffileonpath{\@tempc}{\def\@tempb{!}}{\def\@tempb{?}}% + \fi% + \else% + \def\@tempb{!}% + \fi% + \fi% + }% +} + +%---------------------------------------------------------------------------- +% \ifthenelse{<numtest>{...}}{<true part>}{<false part>}, where <numtest> is: +% \ispositiveinteger (string of one or more digits) +% \isinteger (ditto, with optional leading minus sign) +% \isrealnumber (ditto, with optional decimal point) +% \ispositiverealnumber (ditto, with no leading minus sign) +% +% NB, 0, 0.0, etc consigned positive, -0, -0.0, etc negative by these tests. +%---------------------------------------------------------------------------- +\def\itx@gobbleleadingminus#1{\if-#1\else#1\fi} + +\def\itx@gobblefirstdecimalpoint#1{% + \expandafter\itx@@gobblefirstdecimalpoint% + \romannumeral-`X#1\@empty.\@empty\relax} + +\def\itx@@gobblefirstdecimalpoint#1.#2\@empty#3\relax{#1#2} + +\def\itx@ispositiveinteger#1#2{% + \TE@throw\noexpand\itx@@ispositiveinteger#1\noexpand\@nil% + \noexpand\if!\@tempa#2} + +\def\itx@@ispositiveinteger#1\@nil{% + \def\@tempa{\ifnum9<1#1!\else?\fi}} + +\def\itx@isinteger#1#2{% + \TE@throw\noexpand\itx@@isinteger#1\noexpand\@nil% + \noexpand\if!\@tempa#2} + +\def\itx@@isinteger#1\@nil{% + \expandafter\itx@@ispositiveinteger% + \expandafter{\expandafter\itx@gobbleleadingminus#1}\@nil} + +\def\itx@ispositiverealnumber#1#2{% + \TE@throw\noexpand\itx@@ispositiverealnumber#1\noexpand\@nil% + \noexpand\if!\@tempa#2} + +\def\itx@@ispositiverealnumber#1\@nil{% + \expandafter\itx@@ispositiveinteger% + \expandafter{\expandafter\itx@gobblefirstdecimalpoint% + \expandafter{#1}}\@nil} + +\def\itx@isrealnumber#1#2{% + \TE@throw\noexpand\itx@@isrealnumber#1\noexpand\@nil% + \noexpand\if!\@tempa#2} + +\def\itx@@isrealnumber#1\@nil{% + \expandafter\itx@@ispositiveinteger% + \expandafter{\expandafter\itx@gobblefirstdecimalpoint% + \expandafter{\expandafter\itx@gobbleleadingminus% + \expandafter{#1}}}\@nil} + +% +%============================ end ifthenx.sty ============================ |