%%^^A%%  fontspec-code-fontload.dtx -- part of FONTSPEC <latex3.github.io/fontspec>

% \section{expl3 interface for primitive font loading}
%
% \begin{function}{\@@_primitive_font_set:Nnn,\@@_primitive_font_gset:Nnn}
% \begin{syntax}
% |\@@_primitive_font_set:Nnn| \meta{font cs} \Arg{file/name} \Arg{size (dim.\ expr)}
% \end{syntax}
% Wrapper around \TeX\ \cs{font} primitive.
% \end{function}
%
% \begin{function}{\@@_font_suppress_not_found_error:}
% Wrapper around \XeTeX\/Lua\TeX\ primitive, used to be able to programmatically query font existence.
% \end{function}
%
% \begin{function}[pTF]{\@@_primitive_font_if_null:N}
% \begin{syntax}
% |\@@_primitive_font_if_null:NTF| \meta{font cs} \Arg{true code} \Arg{false code}
% \end{syntax}
% Query whether the \meta{font cs} is the \cs{nullfont}.
% \end{function}
%
% \begin{function}[TF]{\@@_primitive_font_set:Nnn,\@@_primitive_font_gset:Nnn}
% \begin{syntax}
% |\@@_primitive_font_set:NnnTF| \meta{font cs} \Arg{file/name} \Arg{size (dim.\ expr)} \Arg{true code} \Arg{false code}
% \end{syntax}
% Attempts to set the \meta{font cs} and provide branching for success or failure according to whether the font exists.
% \end{function}
%
% \begin{function}[TF]{\@@_primitive_font_if_exist:n}
% \begin{syntax}
% |\@@_primitive_font_if_exist:nTF| \Arg{file/name} \Arg{true code} \Arg{false code}
% \end{syntax}
% Attempts to load the font at the current font size minus 1\,sp with a dummy meta{font cs}
% (\verb|\l_@@_primitive_font|), and branches according to whether the font exists.
% This is intended to be used speculatively before potentially performing additional processing
% steps (e.g., an analysis of available font features) before setting up the `true' font.
% \end{function}
%
% \begin{function}[pTF]{\@@_primitive_font_glyph_if_exist:Nn}
% \begin{syntax}
% |\@@_primitive_font_glyph_if_exist:nTF| \meta{font cs} \Arg{char. number (int.\ expr)} \Arg{true code} \Arg{false code}
% \end{syntax}
% Wrapper around primitive \cs{iffontchar}.
% \end{function}
%
% \begin{function}{\@@_primitive_font_set_hyphenchar:Nn}
% \begin{syntax}
% |\@@_primitive_font_set_hyphenchar:Nn| \meta{font cs} \Arg{char. number (int.\ expr)}
% \end{syntax}
% Setter function around primitive \cs{hyphenchar}.
% \end{function}
%
% \begin{function}{\@@_primitive_font_get_name:N,\@@_primitive_font_current_name:}
% \begin{syntax}
% |\@@_primitive_font_get_name:N| \meta{font cs}
% \end{syntax}
% Wrapper function around \TeX\ primitive \cs{fontname}. The no-argument version is
% equivalent to \verb|\fontname\font|.
% \end{function}
%
% \section{Implementation}
% 
% \iffalse
%    \begin{macrocode}
%<*fontspec>
%    \end{macrocode}
% \fi
%
% \begin{macro}{\@@_primitive_font_set:Nnn,\@@_primitive_font_gset:Nnn}
%    \begin{macrocode}
\cs_set:Npn \@@_primitive_font_set:Nnn #1#2#3
  {
    \font #1 = #2 ~at~ \dim_eval:n {#3} \scan_stop:
  }
%    \end{macrocode}
%    \begin{macrocode}
\cs_set:Npn \@@_primitive_font_gset:Nnn #1#2#3
  {
    \global \font #1 = #2 ~at~ \dim_eval:n {#3} \scan_stop:
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_font_suppress_not_found_error:}
%    \begin{macrocode}
\cs_set:Npn \@@_font_suppress_not_found_error:
  {
    \int_set:Nn \suppressfontnotfounderror {1}
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[pTF]{\@@_primitive_font_if_null:N}
%    \begin{macrocode}
\prg_new_conditional:Nnn \@@_primitive_font_if_null:N {p,TF,T,F}
  {
    \ifx #1 \nullfont
      \prg_return_true:
    \else
      \prg_return_false:
    \fi
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[TF]{\@@_primitive_font_set:Nnn,\@@_primitive_font_gset:Nnn}
%    \begin{macrocode}
\prg_new_conditional:Nnn \@@_primitive_font_set:Nnn {TF,T,F}
  {
    \@@_primitive_font_set:Nnn #1 {#2} {#3}
    \@@_primitive_font_if_null:NTF #1 {\prg_return_false:} {\prg_return_true:}
  }
\prg_new_conditional:Nnn \@@_primitive_font_gset:Nnn {TF,T,F}
  {
    \@@_primitive_font_gset:Nnn #1 {#2} {#3}
    \@@_primitive_font_if_null:NTF #1 {\prg_return_false:} {\prg_return_true:}
  }
\cs_set:Npn \@@_primitive_font_set:Onn   { \exp_last_unbraced:No \@@_primitive_font_set:Nnn }
\cs_set:Npn \@@_primitive_font_set:OnnF  { \exp_last_unbraced:No \@@_primitive_font_set:NnnF }
\cs_set:Npn \@@_primitive_font_gset:Onn  { \exp_last_unbraced:No \@@_primitive_font_gset:Nnn }
\cs_set:Npn \@@_primitive_font_gset:OnnF { \exp_last_unbraced:No \@@_primitive_font_gset:NnnF }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[TF]{\@@_primitive_font_if_exist:n}
%    \begin{macrocode}
\prg_new_conditional:Nnn \@@_primitive_font_if_exist:n {TF,T,F}
  {
    \group_begin:
      \@@_font_suppress_not_found_error:
      \@@_primitive_font_set:Nnn \l_@@_primitive_font {#1} { \f@size pt - 1sp }
      \@@_primitive_font_if_null:NTF \l_@@_primitive_font
        { \group_end: \prg_return_false: }
        { \group_end: \prg_return_true:  }
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[pTF]{\@@_primitive_font_glyph_if_exist:Nn}
%    \begin{macrocode}
\prg_new_conditional:Nnn \@@_primitive_font_glyph_if_exist:Nn {p,TF,T,F}
  {
    \tex_iffontchar:D #1 \int_eval:n {#2} \scan_stop:
      \prg_return_true:
    \else:
      \prg_return_false:
    \fi:
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_primitive_font_set_hyphenchar:Nn}
%    \begin{macrocode}
\cs_new:Nn \@@_primitive_font_set_hyphenchar:Nn
  {
     \tex_hyphenchar:D #1 = \int_eval:n {#2} \scan_stop:
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_primitive_font_get_name:N}
% \begin{macro}{\@@_primitive_font_current_name:}
%    \begin{macrocode}
\cs_new_eq:NN \@@_primitive_font_get_name:N \fontname
\cs_new:Npn \@@_primitive_font_current_name:
  {
    \@@_primitive_font_get_name:N \tex_font:D
  }
%    \end{macrocode}
% \end{macro}
% \end{macro}
%
% \iffalse
%    \begin{macrocode}
%</fontspec>
%    \end{macrocode}
% \fi

\endinput

% /©
% ------------------------------------------------
% The FONTSPEC package  <latex3.github.io/fontspec>
% ------------------------------------------------
% Copyright  2022-2026  The LaTeX project,  LPPL "maintainer"
% Copyright  2004-2022  Will Robertson
% Copyright  2009-2015  Khaled Hosny
% Copyright  2013       Philipp Gesang
% Copyright  2013-2016  Joseph Wright
% ------------------------------------------------
% This package is free software and may be redistributed and/or modified under
% the conditions of the LaTeX Project Public License, version 1.3c or higher
% (your choice): <http://www.latex-project.org/lppl/>.
% ------------------------------------------------
% ©/
