% Copyright (c) 2015-2020 Robert Ryszard Paciorek <rrp@opcode.eu.org>
% 
% MIT License
% 
% Permission is hereby granted, free of charge, to any person obtaining a copy
% of this software and associated documentation files (the "Software"), to deal
% in the Software without restriction, including without limitation the rights
% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
% copies of the Software, and to permit persons to whom the Software is
% furnished to do so, subject to the following conditions:
% 
% The above copyright notice and this permission notice shall be included in all
% copies or substantial portions of the Software.
% 
% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
% SOFTWARE.

% Version 1.0 (2019-05-13): first public release
% Version 1.1 (2020-04-04): bugfix – now |!{...}| works correctly


\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{ehhline}

\RequirePackageWithOptions{hhline}
\RequirePackageWithOptions{etoolbox}

% patch \HH@loop macro from hhline to add !{} syntax
\AtBeginDocument{
  \patchcmd{\HH@loop}{\PackageWarning{hhline}}{%
   \ifx\@tempb!\def\next#1#2{%
       \@tempswafalse\gdef\HH@height{\dimen\thr@@}%
       \if@firstamp\@firstampfalse\else\HH@add{&\omit}\fi%
       \HH@add{#2}%
       \HH@let!}\else
   \PackageWarning{hhline}
  }{}{\PackageWarning{ehhline}{Error patch HH@loop}}
  \patchcmd{\HH@loop}{\fi\fi\fi\fi\fi\fi\fi\fi\fi}{\fi\fi\fi\fi\fi\fi\fi\fi\fi\fi}{}{\PackageWarning{ehhline}{Error patch HH@loop}}
}