%%
%% This is file 'bxcalcize.sty'.
%% 
%% Copyright (c) 2017 Takayuki YATO (aka. "ZR")
%%   GitHub:   https://github.com/zr-tex8r
%%   Twitter:  @zr_tex8r
%%
%% This package is distributed under the MIT License.
%%

%% package declaration
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{bxcalcize}[2017/05/21 v1.0]
\def\bxcy@pkgname{bxcalcize}

%% code guards
\edef\bxcy@restore@codes{%
\catcode45=\the\catcode45%
\catcode46=\the\catcode46%
\catcode47=\the\catcode47%
\endlinechar=\the\endlinechar%
\relax}
\catcode45=12 % <->
\catcode46=12 % <.>
\catcode47=12 % </>
\endlinechar\m@ne
\AtEndOfPackage{
\bxcy@restore@codes
\let\bxcy@restore@codes\relax}


%--------------------------------------- general

%% packages
\RequirePackage{calc}[]
\RequirePackage{etoolbox}[]
\ifx\numdef\@undefined\endinput\fi

%% variables
\newdimen\bxcy@resdim

%--------------------------------------- patches to standard commands

%% to \hspace / \vspace
\csdef{hspace }{
  \@ifstar{\bxcy@with@calc\@hspacer}
   {\bxcy@with@calc\@hspace}
}
\csdef{vspace }{
  \@ifstar{\bxcy@with@calc\@vspacer}
   {\bxcy@with@calc\@vspace}
}

%% to \addvspace
\let\bxcy@org@addvspace\addvspace
\def\addvspace{
  \bxcy@with@calc\bxcy@org@addvspace
}

%% to \\[<len>] (\@newline)
\patchcmd{\@newline}{
  \@gnewline{\vskip#1}
}{
  \setlength\bxcy@resdim{#1}
  \edef\bxcy@tmpa{{\vskip\the\bxcy@resdim}}
  \expandafter\@gnewline\bxcy@tmpa
}{}{% failure
  \PackageWarningNoLine\bxcy@pkgname
   {Patch to \string\@newline\space failed.}
}

%% \bxcy@with@calc
\def\bxcy@with@calc#1#2{
  \setlength\bxcy@resdim{#2}
  \edef\bxcy@tmpa{{\the\bxcy@resdim}}
  \expandafter#1\bxcy@tmpa
}

%--------------------------------------- all done
\endinput
%% EOF