%%%==============================================================================
%% Copyright 2025-present by Alceu Frigeri
%%
%% This work may be distributed and/or modified under the conditions of
%%
%% * The [LaTeX Project Public License](http://www.latex-project.org/lppl.txt),
%%   version 1.3c (or later), and/or
%% * The [GNU Affero General Public License](https://www.gnu.org/licenses/agpl-3.0.html),
%%   version 3 (or later)
%%
%% This work has the LPPL maintenance status *maintained*.
%%
%% The Current Maintainer of this work is Alceu Frigeri
%%
%% This is version {1.0} {2025/05/11}
%%
%% The list of files that compose this work can be found in the README.md file at
%% https://ctan.org/pkg/switch
%%
%%%==============================================================================
\NeedsTeXFormat{LaTeX2e}[2022/06/01]

\ProvidesExplPackage
    {switch}
    {2025/05/11}
    {1.0}
    {switch a constant time switch/case}

%%%%%%%
%%%
%%% Just an attempt of having my packages info in a regular way
%%% Idea being: { <pck-name> / pkg info } for each and all.
%%%
%%%%%%%
\keys_define:nn { switch / pkg info}
  {
     name        .code:n = {switch} ,
     prefix      .code:n = {switch} ,
     date        .code:n = {2025/05/11},
     version     .code:n = {1.0} ,
     description .code:n = {switch a constant time switch/case}
  }
\cs_if_exist:NF \PkgInfo 
  {
    \NewDocumentCommand \PkgInfo {mm} { \keys_set:nn {#1 / pkg info}{#2} } 
    \NewDocumentCommand \PkgDescription {m} 
      { \noindent Package~ \textbf{\PkgInfo{#1}{name}}~Version:~\PkgInfo{#1}{version}~ -~ \PkgInfo{#1}{date}\par \emph{\PkgInfo{#1}{description}}~\par } 
  }  
%%%%%%%
%%% End of cut-n-paste
%%%%%%%

\cs_new_protected:Npn \switch_new:Nn #1#2
  {
    \cs_new:Npn #1 ##1 
      {
        \cs_if_exist_use:cF { \cs_to_str:N #1 _case_ ##1 : }
          { #2 }
      }
  }
\cs_new_eq:NN \newswitch \switch_new:Nn
  
\cs_new_protected:Npn \switch_addcase:Nnn #1#2#3
  {
    \cs_new:cpn { \cs_to_str:N #1 _case_ #2 : } {#3}
  }
\cs_new_eq:NN \addcase \switch_addcase:Nnn


%%%% 
%%%% TeX implementation
%%%%
%%\makeatletter
%%\def\newswitch#1#2{\def#1##1{\ifcsname\string#1@case@##1\endcsname\csname\string#1@case@##1\endcsname\else#2\fi}}%
%%\def\addcase#1#2#3{\expandafter\def\csname\string#1@case@#2\endcsname{#3}}%
%%\makeatother