% \def\filename{rkeyval.dtx}
% \def\fileversion{2.00}
% \def\filedate{2004/06/28}
%
% \iffalse meta-comment
%
% American Mathematical Society
% Technical Support
% Publications Technical Group
% 201 Charles Street
% Providence, RI 02904
% USA
% tel: (401) 455-4080
% (800) 321-4267 (USA and Canada only)
% fax: (401) 331-3842
% email: tech-support@ams.org
%
% Copyright 2001, 2010 American Mathematical Society.
%
% This work may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version 1.3c
% 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 1.3c or later is part of all distributions of LaTeX
% version 2005/12/01 or later.
%
% This work has the LPPL maintenance status `maintained'.
%
% The Current Maintainer of this work is the American Mathematical
% Society.
%
% \fi
%
% \iffalse
%<*driver>
\documentclass[draft,oneside]{amsdtx}
\pagestyle{myheadings}
\makeatletter
\DeclareRobustCommand{\fld}{\@category@index{field}}
\makeatother
\DoNotIndex{\@emptytoks,\@temptokenb}
\CodelineIndex
\begin{document}
\title{The \pkg{rkeyval} package:\protect\linebreak[1]
Syntactically restricted key-value scanning}
\author{Michael Downes and David M. Jones\\American Mathematical Society}
\date{Version \fileversion, \filedate}
\DocInput{rkeyval.dtx}
\PrintIndex
\end{document}
%</driver>
% \fi
%
% \MakeShortVerb{\|}
%
% \maketitle
% \markboth{The \protect\pkg{rkeyval} package}
% {Version \protect\fileversion, \protect\filedate}
%
% \tableofcontents
%
% \section{Introduction}
%
% The \pkg{rkeyval} package provides functions for scanning key-value
% notation similar to the kind of scanning supported by the standard
% \pkg{keyval} package. However, the syntax is more restrictive in
% order to make some improved error-checking possible. In particular,
% if a comma is omitted between two instances of |key={value}|
% form, the \cn{RestrictedSetKeys} command will spot the missing
% comma and issue a suitable error message (and it will be given at
% the point where the missing comma is detected, before reading any
% further in the \tex/ file). The standard \cn{setkeys} command, by
% contrast, will append the second key name to the value of the first
% key and discard the second value, without any notification to the
% user that anything has gone wrong. But that is partly because the
% standard \cn{setkeys} command allows implied values and does not
% require braces around explicit values (except when necessary to
% hide material that has a syntactic resemblance to a key-value
% pair). With \cn{RestrictedSetKeys} the value must always be present
% and it must be enclosed in braces.
%
%^^A Maybe commas should be optional.
%
% Further restrictions of the \cn{RestrictedSetKeys} command and its
% companion commands reduce memory consumption in certain ways.
% Defining a key creates only one control sequence, a container for
% holding the value. Processing of key values is normally limited to
% storing a value given by the user; any additional processing must
% be supplied separately by the programmer.
%
% Generally speaking, the error-checking done by
% \cn{RestrictedSetKeys} is better for applications where all the
% keys are expected to have textual values, while \cn{setkeys} is
% better when one wants to silently recover as far as possible from
% syntactic errors, instead of notifying the user of the errors; or
% when keys have nontrivial default values (i.e., not empty) or other
% kinds of special processing.
%
% \begin{verbatim}
% \RestrictedSetKeys{setup-code}{group}{code}{key={val}, ...}
%\end{verbatim}
% Normally \cn{RestrictedSetKeys} simply carries out the following
% assignment for each key-value pair:
% \begin{verbatim}
% \def\group'key{val}
%\end{verbatim}
% The first argument is normally empty, but the exact nature of the
% warnings given and other aspects of the processing can be affected
% by putting extra setup code there. The \pkg{amsrefs} package uses
% this to implement a copying operation where field name and value
% are written out immediately to another file instead of being stored
% in the usual way.
%
% Some examples for defining the key names associated with a given
% group. This defines ``title'' as a recognized key for the \fn{bib}
% group:
% \begin{verbatim}
% \DefineSimpleKey{bib}{title}
%\end{verbatim}
% If a key is defined with \cs{DefineSimpleKey}, the result of using
% the same key more than once in a single entry will be an error
% message.
%
% This defines ``title'' to be a repeatable key:
% \begin{verbatim}
% \DefineSupersedingKey{bib}{title}
%\end{verbatim}
% If it occurs more than once, the last value supersedes the earlier
% ones, instead of getting an error. This variation is not needed for
% simple usage, but in more complicated situations where key values
% are combined from multiple sources, it may be useful.
%
% This defines ``author'' to be a repeatable key, with each value
% being appended to a list of values:
% \begin{verbatim}
% \DefineAdditiveKey{bib}{author}{\name}
%\end{verbatim}
% The third argument specifies a wrapper function that should be
% applied to each item in the list. I.e., suppose that two author
% names are given:
% \begin{verbatim}
% author={Smith, J. Q.},
% author={Taylor, X. Y.},
%\end{verbatim}
% Then they will be stored in the form
% \begin{verbatim}
% \name{Smith, J. Q.}\name{Taylor, X. Y.}
%\end{verbatim}
%
% This defines ``transition'' to be a dummy key with a value that is
% superficially nonempty but effectly empty:
% \begin{verbatim}
% \DefineDummyKey{bib}{transition}
%\end{verbatim}
% Defining a dummy key like this can be useful in dealing with
% certain boundary situations that sometimes arise.
%
% \StopEventually{}
%
% \section{Implementation}
% Standard declaration of package name and date.
% \begin{macrocode}
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{rkeyval}[2004/05/05 v1.08]
% \end{macrocode}
%
% \begin{macro}{\@xp}
% \begin{macro}{\@nx}
% \begin{macrocode}
\let\@xp\expandafter
\let\@nx\noexpand
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@gobblethree}
% \begin{macro}{\@nilgobble}
% Not in the \latex/ kernel yet.
% \begin{macrocode}
\long\def\@gobblethree#1#2#3{}
\long\def\@nilgobble#1\@nil{}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@emptytoks}
% Using \cs{@ifundefined} here avoids problems with really old
% versions of \latex/ that choke on \cs{newtoks} if it is written
% directly in the false branch of a conditional.
% \begin{macrocode}
\@ifundefined{@emptytoks}{\csname newtoks\endcsname\@emptytoks}{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@temptokenb}
% \begin{macrocode}
\@ifundefined{@temptokenb}{\csname newtoks\endcsname\@temptokenb}{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@append}
% \begin{macrocode}
\def\@append#1#2#3{\@xp\def\@xp#2\@xp{#2#1{#3}}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\star@}
% Test for a trailing option marked by a star. Usage:
% \begin{verbatim}
% \newcommand{\blub}[1]{\star@{\blubaux{#1}}{default}}
%\end{verbatim}
% Arg 1 of \cs{star@} is the code to
% be run, arg 2 is the default value of the option (could be empty).
% If arg 1 is \ncn{moo}, this test discards a star and expands to
% \ncn{moo} if a star is found, or expands to |\moo{#2}| if
% not. As the example shows, arg 1 need not be a single token.
% \begin{macrocode}
\def\star@#1#2{%
\def\star@a##1{#1}%
\def\star@b{#1{#2}}%
\futurelet\@let@token\star@test
}
\def\star@test{\ifx*\@let@token \let\star@b\star@a\fi \star@b}
% \end{macrocode}
%
% Please note: If there is a space before the star, then the star is
% not treated as an option char.
%
% Why use a star? Since it's already part of standard \latex/
% command syntax, it's unlikely to suffer from catcode changes.
%
% Why not just put the star at the beginning in the usual way? It
% seemed to me that the lack of a trailing option
% feature was a deficiency in current \latex/ and could be given an
% experimental implementation in a package like this without any
% adverse effect on existing documents.
% \end{macro}
%
% Ensure non-weird catcode for relevant characters.
% \begin{macrocode}
\@ifundefined{NormalCatcodes}{\RequirePackage{pcatcode}\relax}{}
\PushCatcodes\NormalCatcodes
% \end{macrocode}
%
% \begin{macro}{\extract@group}
% Extracts ``group'' from |\group'field|.
% \begin{macrocode}
\def\extract@group#1{%
\@xp\extract@group@a\string#1\@nil
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\extract@group@a}
% \begin{macrocode}
\def\extract@group@a#1#2'{#2\@nilgobble}
% \end{macrocode}
% \end{macro}
%
% \section{Data structures}
%
% The result of scanning the key/value pairs is an assignment statement
% for \cs{rsk@toks}. For example, consider the entry
% \begin{verbatim}
% \bib{LelekZ1962}{article}{
% author={Lelek, A.},
% author={Zaremba, D.},
% title={Dimensions of irreducible ...},
% journal={Fund. Math.},
% date={1962/63},
% }
%\end{verbatim}
% The scanned result is to assign
% \begin{verbatim}
% \global\rsk@toks{%
% \set:bib'author{Lelek, A.}{}%
% \set:bib'author{Zaremba, D.}{}%
% \set:bib'title{Dimensions of irreducible ...}{}%
% \set:bib'journal{Fund. Math.}{}%
% \set:bib'date{1962/63}{}%
% }
%\end{verbatim}
% The extra empty arguments on each line are for auxiliary
% properties (see below).
% What happens thereafter with \cs{rsk@toks} depends on the code in
% the last arg of \cs{RestrictedSetKeys}.
%
% \section{Auxiliary properties}
%
% Unfortunately, the previous section isn't the entire story. In
% addition to the values of each field, we need to store a set of
% auxiliary properties associated with those values. Note that
% properties are explicitly associated with \emph{values}, not with
% keys, because each value of an additive key could have different
% properties.
%
% All such extra data will be stored in a special field named
% ``aux'', with embedded tags to indicate which field each piece of
% the \fld{aux} field is associated with. The extra bits can be
% extracted on demand using standard techniques, and the primary
% value of each field is not burdened with any attachments, so that
% comparisons or scanning of the field contents can remain as
% simple as possible.
%
% Thus in practice there is at least one bit of auxiliary information
% in every bib item, and our previous example would have the title
% language indicated:
% \begin{verbatim}
% \DSK@def\bib'title{Eine Bemerkung zur Darstellung von Polynomen
% \"{u}ber Verb\"{a}nden}%
% \@append\bib'title\bib'aux{\selectlanguage{german}}%
%\end{verbatim}
%
% \begin{macro}{\set@property}
% \begin{macrocode}
\def\set@property#1{%
\begingroup
\edef\@tempa{\extract@group#1}%
\edef\@tempa{%
\@nx\@append\@nx#1\@xp\@nx\csname \@tempa,aux\endcsname
}%
\@xp\endgroup
\@tempa
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\get@property}
% \begin{macrocode}
% \get@property\destination\bib'title
\def\get@property#1#2{%
\get@nth@property#1#2\m@ne
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\get@nth@property}
% \begin{macrocode}
% \get@nth@property\destination\bib'title N
\def\get@nth@property#1#2#3{%
\begingroup
\edef\@tempa{\extract@group#2}%
\@tempcnta#3\relax
\@tempcntb\z@
\@xp\scan@properties\@xp#2\csname \@tempa,aux\endcsname
\edef\@tempa{\def\@nx#1{\@tempa}}%
\@xp\endgroup
\@tempa
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\scan@properties}
% \begin{macrocode}
\def\scan@properties#1#2{%
\begingroup
\def\@tempa{#1}%
\let\@tempc\@empty
\@xp\find@property #2 \@nil\@nil
\edef\@tempa{\def\@nx\@tempa{\@tempc}}%
\@xp\endgroup
\@tempa
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\find@property}
% \begin{macrocode}
\def\find@property#1#2{%
\ifx\@nil#1%
\else
\def\@tempb{#1}%
\ifx\@tempa\@tempb
\ifnum\@tempcnta<\z@
\def\@tempc{#2}%
\else
\advance\@tempcntb\@ne
\ifnum\@tempcntb=\@tempcnta
\def\@tempc{#2}%
\fi
\fi
\fi
\@xp\find@property
\fi
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\reset@property}
% \begin{macrocode}
\def\reset@property#1#2{%
\reset@nth@property#1\m@ne{#2}%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\reset@nth@property}
% \begin{macrocode}
% \reset@nth@property\bib'title N VALUE
\def\reset@nth@property#1#2#3{%
\begingroup
\edef\@tempa{\extract@group#1}%
\@tempcnta#2\relax
\@temptokena{#3}%
\toks@\@emptytoks
\@tempcntb\z@
\@xp\reset@scan\@xp#1\csname \@tempa,aux\endcsname
\edef\@tempa{%
\def\@xp\@nx\csname \@tempa,aux\endcsname{\the\toks@}%
}%
\@xp\endgroup
\@tempa
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\reset@scan}
% \begin{macrocode}
\def\reset@scan#1#2{%
\begingroup
\def\@tempa{#1}%
\@xp\reset@scan@a #2 \@nil\@nil
\edef\@tempa{\toks@{\the\toks@}}%
\@xp\endgroup
\@tempa
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\find@property}
% \begin{macrocode}
\def\reset@scan@a#1#2{%
\ifx\@nil#1%
\else
\def\@tempb{#1}%
\ifx\@tempa\@tempb
\ifnum\@tempcnta<\z@
\@temptokenb\@temptokena
\else
\advance\@tempcntb\@ne
\ifnum\@tempcntb=\@tempcnta
\@temptokenb\@temptokena
\fi
\fi
\else
\@temptokenb{#2}%
\fi
\edef\@tempb{%
\toks@{\the\toks@ \@nx#1{\the\@temptokenb}}%
}%
\@tempb
\@xp\reset@scan@a
\fi
}
% \end{macrocode}
% \end{macro}
%
% \section{Some machinery for finite state automata}
%
% Coincidentally I needed to write two finite state automaton parsers
% for two related packages, so after writing them separately I spent
% some time analyzing the code fragments they shared in common and
% abstracted them so that the cs names could be shared.
%
% \begin{macro}{\fsa@l}
% FSA lookahead.
% \begin{macrocode}
\def\fsa@l{\futurelet\@let@token\fsa@t}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fsa@b}
% FSA bypass a token. Don't delete the space at the end!
% \begin{macrocode}
\def\fsa@b{\afterassignment\fsa@l \let\@let@token= }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fsa@c}
% FSA copy a token (not space, bgroup, egroup).
% \begin{macrocode}
\def\fsa@c#1{\aftergroup#1\fsa@l}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fsa@n}
% FSA next action. This is just a placeholder definition.
% \begin{macrocode}
\let\fsa@n\@empty
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\fsa@t}
% FSA test. This is just a placeholder definition.
% \begin{macrocode}
\let\fsa@t\@empty
% \end{macrocode}
% \end{macro}
%
% \section{Now some of the real work}
%
% \begin{macro}{\rsk@toks}
% \begin{macrocode}
\newtoks\rsk@toks
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rkvIfEmpty}
% Beginning here.
% \begin{macrocode}
\def\rkvIfEmpty#1#2{%
\@xp\ifx\csname#1'#2\endcsname\@empty
\@xp\@firstoftwo
\else
\@xp\@secondoftwo
\fi
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rkvIfAdditive}
% \begin{macrocode}
\def\rkvIfAdditive#1{%
\@xp\let\@xp\@let@token \csname \rkv@setter#1\endcsname
\afterassignment\@nilgobble
\@xp\let\@xp\@let@token \@let@token \@empty\@empty\@nil
\ifx\@let@token\DSK@append
\@xp\@firstoftwo
\else
\@xp\@secondoftwo
\fi
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rkv@setter}
% It irritates me that I can't embed the \ncn{csname} and
% \ncn{endcsname} in here.
% \begin{macrocode}
\def\rkv@setter#1{set:\@xp\@gobble\string#1}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rkv@DSAK}
% Define a simple, superseding, or additive key.
% \begin{macrocode}
\def\rkv@DSAK#1#2{%
\addto@group@reset#1{\let#1\@empty}%
\edef\@tempa{\def\csname \rkv@setter#1\endcsname}%
\@tempa{#2#1}%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rkv@DDK}
% This function is used for a dummy key whose value (expansion)
% should be empty but that should appear non-empty to
% \cs{rkvIfEmpty}.
% \begin{macrocode}
\def\rkv@DDK#1{%
\addto@group@reset#1{\def#1{\@empty}}%
\@xp\let\csname \rkv@setter#1\endcsname\@gobble
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\DSK@def}
% \begin{macrocode}
\def\DSK@def#1{%
\ifx#1\@empty\else
\PackageWarningNoLine{rkeyval}%
{Key \string#1 should not be repeated}%
\fi
\DSK@redef#1%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\DSK@redef}
% We weed out empty field values for consistency with
% \cs{DSK@append}.
% \begin{macrocode}
\def\DSK@redef#1#2{%
\@ifempty{#2}{\@gobble}{%
\def#1{#2}%
\set@property#1
}%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\init@group@reset}
% \begin{macrocode}
\def\init@group@reset#1{%
\begingroup
\edef\@tempb{\@xp\@nx\csname #1@reset\endcsname}%
\@xp\ifx\@tempb\relax
\@xp\xdef\@tempb{\let \csname #1,aux\endcsname\@nx\@empty}
\fi
\endgroup
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\addto@group@reset}
% \begin{macrocode}
\def\addto@group@reset#1{%
\begingroup
\edef\@tempa{\extract@group#1}%
\init@group@reset\@tempa
\edef\@tempa{%
\@nx\g@addto@macro\@xp\@nx\csname\@tempa @reset\endcsname
}%
\@xp\endgroup
\@tempa
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\DefineSimpleKey}
% \begin{macrocode}
\newcommand{\DefineSimpleKey}[2]{%
\@xp\rkv@DSAK
\csname #1'#2\endcsname
{\DSK@def}%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\DefineSupersedingKey}
% \begin{macrocode}
\newcommand{\DefineSupersedingKey}[2]{%
\@xp\rkv@DSAK
\csname #1'#2\endcsname
{\DSK@redef}%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\DefineAdditiveKey}
% \begin{macrocode}
\newcommand{\DefineAdditiveKey}[3]{%
\@xp\rkv@DSAK
\csname #1'#2\endcsname
{\DSK@append#3}%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\DSK@append}
% We weed out empty field values (e.g., |editor={}| or
% \verb*|editor={ }|) because otherwise an additive field could
% end up with a value like |\name{}| which appears non-empty to
% \cs{rkvIfEmpty} but produces no output on the page.
% \begin{macrocode}
\def\DSK@append#1#2#3{%
\@ifempty{#3}{\@gobble}{%
\@append#1#2{#3}%
\set@property#2
}%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\DefineDummyKey}
% \begin{macrocode}
\newcommand{\DefineDummyKey}[2]{%
\@xp\rkv@DDK \csname #1'#2\endcsname
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\RestrictedSetKeys}
% \begin{macrocode}
\newcommand{\RestrictedSetKeys}[3]{%
\global\rsk@toks\@xp{\csname #2@reset\endcsname}%
\def\rsk@finish{#3}%
\gdef\rsk@set{\@xp\rsk@set@a\csname#2'}%
#1\relax
\begingroup
\rsk@changecase
\aftergroup\rsk@set
% \end{macrocode}
% Start by removing the opening brace.
% \begin{macrocode}
\let\fsa@t\rsk@z
\fsa@l
}
% \end{macrocode}
% \end{macro}
%
% The aftergroup tokens end up looking like this:
% \begin{verbatim}
% \lowercase{\rsk@set FIELDNAME\endcsname}
% --> \@xp\rsk@set@a\csname bib'fieldname\endcsname
% --> \rsk@set@a\bib'abcdef
%\end{verbatim}
%
% \begin{macro}{\rsk@unknown@key}
% \begin{macrocode}
\def\rsk@unknown@key#1{%
\PackageWarning{rkeyval}{Unknown key: \string#1}%
\@xp\def\csname\rkv@setter#1\endcsname {\DSK@redef#1}%
}
% \end{macrocode}
% \end{macro}
%
% \section{The state machine}
%
%\begin{verbatim}
% State 0: Skip opening brace (\rsk@z).
% space -> 0
% { -> 2
% other -> error "Missing open brace"
%
% State 1: Skip comma (\rsk@a).
% space -> 1
% \par -> 1
% comma -> 2
% @ -> read optional arg; 1
% } -> 6
% other -> error "Missing comma"; 2
%
% State 2: Find field name (\rsk@b).
% space -> 2
% \par -> 2
% comma -> 2
% letter -> 3
% { -> error "Missing key name"; 4
% } -> 6
% other -> error "Invalid key name character"; 2
%
% State 3: Scan field name (\rsk@c).
% letter -> 3
% comma -> error "Invalid key name character"; 3
% equal -> 4
% other punct -> 3
% space -> 4
% { -> error "Missing equal sign"; 4
% } -> error "Missing equal sign"; 4
% other -> error "Invalid key name character"; 3
%
% State 4: Skip equals (\rsk@d).
% space -> 4
% equal -> 4
% { -> 5
% other -> error "Missing { for value of current key"; 5
%
% State 5: Read field value (\rsk@set@a).
% any -> 1
%
% State 6: Done (\rsk@end).
%\end{verbatim}
%
% \begin{macro}{\rsk@z}
% State 0: Skip opening brace.
% \begin{macrocode}
\def\rsk@z{%
\ifx\bgroup\@let@token
\let\fsa@t\rsk@b
\let\fsa@n\fsa@b
\else
\ifx\@sptoken\@let@token
\let\fsa@n\fsa@b
\else
\rsk@errf
\fi
\fi
\fsa@n
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@a}
% State 1: Skip comma.
% \begin{macrocode}
\def\rsk@a{%
\ifx\@let@token\@sptoken
\let\fsa@n\fsa@b
\else
\ifx\@let@token\par
\let\fsa@n\fsa@b
\else
\ifx,\@let@token
\endgroup
\let\fsa@t\rsk@b
\let\fsa@n\fsa@b
\else
\ifx\egroup\@let@token
\endgroup
\let\fsa@n\rsk@end
\else
\endgroup
\let\fsa@n\rsk@erraa
\fi
\fi
\fi
\fi
\fsa@n
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@b}
% State 2: Find field name.
%
% Allow \cs{par} here to permit a blank line after
% the end of one key-val pair and the start of the next (perhaps to
% break up a long list into sections).
% \begin{macrocode}
\def\rsk@b{%
\ifcat\@nx\@let@token A%
\let\fsa@t\rsk@c
\let\fsa@n\fsa@c
\else
\ifx\@sptoken\@let@token
\let\fsa@n\fsa@b
\else
\rsk@bb
\fi
\fi
\fsa@n
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@bb}
% \begin{macrocode}
\def\rsk@bb{%
\ifx,\@let@token
\let\fsa@n\fsa@b
\else
\ifx\bgroup\@let@token
\let\fsa@n\rsk@errb
\else
\ifx\egroup\@let@token
\let\fsa@n\rsk@end
\else
\ifx\par\@let@token
\let\fsa@n\fsa@b
\else
\let\fsa@n\rsk@errc
\fi
\fi
\fi
\fi
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@c}
% State 3: Scan field name.
% \begin{macrocode}
\def\rsk@c{%
\ifcat\@nx\@let@token A%
\let\fsa@n\fsa@c
\else
\ifx\@sptoken\@let@token
\let\fsa@t\rsk@d
\let\fsa@n\fsa@b
\else
\ifx=\@let@token
\let\saw@equal T%
\let\fsa@t\rsk@d
\let\fsa@n\fsa@b
\else
\rsk@cb
\fi
\fi
\fi
\fsa@n
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@cb}
% \begin{macrocode}
\def\rsk@cb{%
\ifx,\@let@token
\let\fsa@n\rsk@errc
\else
\ifcat\@nx\@let@token .%
\let\fsa@n\fsa@c
\else
\ifx\bgroup\@let@token
\let\fsa@n\rsk@noequal
\else
\ifx\egroup\@let@token
\let\fsa@n\rsk@noequal
\else
\let\fsa@n\rsk@errc
\fi
\fi
\fi
\fi
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\saw@equal}
% \begin{macrocode}
\let\saw@equal=F
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@d}
% State 4: Skip equals.
%
% If no equal sign ever came
% along, then give a warning about it and set \cs{saw@equal} to true
% so that when \cs{rsk@noequal} cycles through again it will take the
% other branch.
% \begin{macrocode}
\def\rsk@d{%
\ifx\bgroup\@let@token
\ifx\saw@equal T%
\aftergroup\endcsname
\rsk@endcase
\let\fsa@n\endgroup
\else
\let\saw@equal T%
\let\fsa@n\rsk@noequal
\fi
\else
\ifx\@sptoken\@let@token
\let\fsa@n\fsa@b
\else
\ifx=\@let@token
\let\saw@equal T%
\let\fsa@n\fsa@b
\else
\let\fsa@n\rsk@erre
\fi
\fi
\fi
\fsa@n
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@casesensitive}
% \begin{macrocode}
\def\rsk@casesensitive{%
\let\rsk@changecase\@empty
\let\rsk@endcase\@empty
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@startlc}
% \begin{macrocode}
\def\rsk@startlc{\aftergroup\lowercase\aftergroup{\iffalse}\fi}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@endlc}
% \begin{macrocode}
\def\rsk@endlc{\iffalse{\fi\aftergroup}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@lowercase}
% \begin{macrocode}
\def\rsk@lowercase{%
\let\rsk@changecase\rsk@startlc
\let\rsk@endcase\rsk@endlc
}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
\rsk@lowercase
% \end{macrocode}
%
% \begin{macro}{\rsk@resume}
% Here we get improved reporting of error context by changing
% end-of-line to be different from normal space. If we don't find a
% comma on the current line, assume it is an error.
% \begin{macrocode}
\def\rsk@resume{%
\begingroup
\rsk@changecase
\aftergroup\rsk@set
\let\fsa@t\rsk@a
\begingroup
\catcode\endlinechar=\active
\lccode`\~=\endlinechar
\lowercase{\let~\par}%
\fsa@l
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@set@a}
% State 5: Read field value.
% \begin{macrocode}
\def\rsk@set@a#1#2{%
\star@{\rsk@set@b#1{#2}}{}%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@set@b}
% \begin{macrocode}
\def\rsk@set@b#1#2#3{%
\@xp\ifx \csname\rkv@setter#1\endcsname \relax
\rsk@unknown@key#1%
\fi
\edef\@tempa{\@xp\@nx\csname \rkv@setter#1\endcsname}%
\toks@\@xp{\@tempa{#2}{#3}}%
\edef\@tempa{%
\global\rsk@toks{\the\rsk@toks \the\toks@}%
}%
\@tempa
\rsk@resume
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@end}
% State 6: Done.
%
% Lets see, now why did I add this?
% \begin{macrocode}
\def\rsk@end{%
\global\let\rsk@set\rsk@terminate
\rsk@endcase
\endgroup
\endcsname
\afterassignment\rsk@finish
\toks@\bgroup
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@terminate}
% \begin{macrocode}
\def\rsk@terminate{\@xp\@gobble\csname}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\NoCommaWarning}
% \begin{macrocode}
\def\NoCommaWarning{\PackageWarning{rkeyval}{Missing comma}}%
% \end{macrocode}
% \end{macro}
%
%% % \begin{macro}{\NoCommaError}
%% % \begin{macrocode}
%% \def\NoCommaError{\rsk@err{Missing comma}\@ehc}
%% % \end{macrocode}
%% % \end{macro}
%
% \begin{macro}{\rsk@nocomma}
% \begin{macrocode}
\def\rsk@nocomma{\NoCommaWarning}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@err}
% \begin{macrocode}
\def\rsk@err{\PackageError{rkeyval}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@errf}
% \begin{macrocode}
\def\rsk@errf{\rsk@err{Missing open brace}\@ehc\rsk@b}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@erraa}
% \begin{macrocode}
\long\def\rsk@erraa{\rsk@nocomma \let\fsa@t\rsk@b \fsa@l}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@errb}
% \begin{macrocode}
\def\rsk@errb{\rsk@err{Missing key name}\@ehc\rsk@d}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@errc}
% \begin{macrocode}
\def\rsk@errc{\rsk@err{Invalid key name character}\@ehc\fsa@b}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\rsk@noequal}
% \begin{macrocode}
\def\rsk@noequal{\rsk@err{Missing equal sign}\@ehc\rsk@d}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\rsk@erre}
% In this case we guess that the value is without braces but probably
% terminated with a comma. We want to scan up to the comma in order
% to get back in synch.
% \begin{macrocode}
\def\rsk@erre#1,{%
\rsk@err{Missing open brace for key value}\@ehc
\iffalse{\fi
\endgroup
\endcsname
\rsk@endcase }{#1},%
}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
\PopCatcodes
% \end{macrocode}
%
% The usual \cs{endinput} to ensure that random garbage at the end of
% the file doesn't get copied by \fn{docstrip}.
% \begin{macrocode}
\endinput
% \end{macrocode}
%
% \CheckSum{871}
% \Finale