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+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