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% This macro source file is from the four volume series
% "TeX in Practice" by Stephan von Bechtolsheim, published
% 1993 by Springer-Verlag, New York.
% Copyright 1993 Stephan von Bechtolsheim.
% No warranty or liability is assumed.
% This macro may be copied freely if no fees other than
% media cost or shipping charges are charged and as long
% as this copyright and the following source code itself
% is not changed. Please see the series for further information.
%
% Version: 1.0
% Date: May 1, 1993
%
%
% This source code is documented in 25.1.19.1, p. III-341.
% Original source in file "macros5.TEX", starting line 1398.
\wlog{L: "stswitch.tip" ["macros5.TEX," l. 1398, p. III-341]}%
% This file DOES belong to format "texip."
\InputD{compst.tip}
\catcode`\@ = 11
\newcount\@StringSwitchMatchCount
\def\StringSwitch #1#2{%
    \edef\@StringSwitchMasterString{#1}%
    \if\EmptyStringConditional{#1}%
        \errmessage{\string\StringSwitch: master string
            must not be the empty string.}%
    \fi
    \def\@StringSwitchMatchCommonCode{#2}%
    \@StringSwitchMatchCount = 0
    \@StringSwitch  
}
\def\@StringSwitchOne #1#2{%
    \def\@StringSwitchString{#1}%
    \def\@StringSwitchAction{#2}%
}
\def\@StringSwitch #1{%
    \@StringSwitchOne #1%
    \if\EmptyStringConditional{\@StringSwitchString}%
        \ifcase\@StringSwitchMatchCount
            \@StringSwitchAction
        \or
        \else
            \errmessage{\string\StringSwitch: double match.}%
        \fi
        \def\@StringSwitchNext{}%
    \else
        \if\StringsEqualConditional{\@StringSwitchMasterString}%
            {\@StringSwitchString}%
            \advance\@StringSwitchMatchCount by 1
            \@StringSwitchMatchCommonCode
            \@StringSwitchAction
        \fi
        \def\@StringSwitchNext{\@StringSwitch}%
    \fi 
    \@StringSwitchNext
}
\catcode`\@ = 12