atbeginend.sty revision 273eafe6bf1d6f7e307eada091fef9a80ab1f440
%
% Copyright 2003-2005 The Apache Software Foundation or its licensors,
% as applicable.
%
% Licensed under the Apache License, Version 2.0 (the "License");
% you may not use this file except in compliance with the License.
% You may obtain a copy of the License at
%
%
% Unless required by applicable law or agreed to in writing, software
% distributed under the License is distributed on an "AS IS" BASIS,
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
% See the License for the specific language governing permissions and
% limitations under the License.
% defines
% \BeforeBegin{environment}{code-to-execute}
% \BeforeEnd {environment}{code-to-execute}
% \AfterBegin {environment}{code-to-execute}
% \AfterEnd {environment}{code-to-execute}
%
% Save \begin and \end to \BeginEnvironment and \EndEnvironment
\let\BeginEnvironment=\begin
\let\EndEnvironment=\end
\def\IfUnDef#1{\expandafter\ifx\csname#1\endcsname\relax}
% Null command needed to for \nothing{something}=.nothing.
\def\NullCom#1{}
\def\begin#1{%
%
% if defined \BeforeBeg for this environment, execute it
\IfUnDef{BeforeBeg#1}\else\csname BeforeBeg#1\endcsname\fi%
%
%
%
\IfUnDef{AfterBeg#1}% This is done to skip the command for environments
% which can take arguments, like multicols; YOU MUST NOT
% USE \AfterBegin{...}{...} for such environments!
\let\SaveBegEng=\BeginEnvironment%
\else%
% Start this environment
\BeginEnvironment{#1}%
% and execute code after \begin{environment}
\csname AfterBeg#1\endcsname%
%
\let\SaveBegEng=\NullCom%
\fi%
\SaveBegEng{#1}%
}
\def\end#1{%
%
% execute code before \end{environment}
\IfUnDef{BeforeEnd#1}\else\csname BeforeEnd#1\endcsname\fi%
%
% close this environment
\EndEnvironment{#1}%
%
% and execute code after \begin{environment}
\IfUnDef{AfterEnd#1}\else\csname AfterEnd#1\endcsname\fi%
}
%% Now, define commands
% \BeforeBegin{environment}{code-to-execute}
% \BeforeEnd {environment}{code-to-execute}
% \AfterBegin {environment}{code-to-execute}
% \AfterEnd {environment}{code-to-execute}
\def\BeforeBegin#1#2{\expandafter\gdef\csname BeforeBeg#1\endcsname
{#2}}
\def\BeforeEnd #1#2{\expandafter\gdef\csname BeforeEnd#1\endcsname
{#2}}
\def\AfterBegin #1#2{\expandafter\gdef\csname AfterBeg#1\endcsname {#2}}
\def\AfterEnd #1#2{\expandafter\gdef\csname AfterEnd#1\endcsname{#2}}