um-code-main.dtx

%%^^A%% um-code-main.dtx -- part of UNICODE-MATH <wspr.io/unicode-math>
%%^^A%% Definition of `\setmainfont`.

% \section{The main \cs{setmathfont} macro}
%
%    \begin{macrocode}
%<*package>
%    \end{macrocode}
%
% \begin{macro}{\@@_setmathfont:nn}
% \darg{keyval options}
% \darg{font name/file}
%    \begin{macrocode}
\@@_cs_new:Nn \@@_setmathfont:nn
  {
%    \end{macrocode}
% \begin{itemize}
% \item Initialise all local variables.
% \item
% Erase any conception \LaTeX\ has of previously defined math symbol fonts;
% this allows \cmd\DeclareSymbolFont\ at any point in the document.
% \item
% Grab the current size information:
% (is this robust enough? Maybe it should be preceded by \cmd\normalsize).
% The macro \cmd\S@\meta{size}
% contains the definitions of the sizes used for maths letters, subscripts and subsubscripts in
% \cmd\tf@size, \cmd\sf@size, and \cmd\ssf@size, respectively.
% \end{itemize}
%    \begin{macrocode}

    \@@_init:n {#2}
    \cs_set_eq:NN \glb@currsize \scan_stop:
    \cs_if_exist:cF { S@ \f@size } { \calculate@math@sizes }
    \use:c { S@ \f@size }

    \keys_set_known:nnN {unicode-math} {#1} \l_@@_unknown_keys_clist

    \bool_if:NT \g_@@_init_bool \@@_fontspec_trial_font:
    \bool_if:NT \g_@@_init_bool \@@_declare_math_sizes:

    \@@_fontspec_select_font:
    \@@_setup_math_fam:
    \bool_if:NT \g_@@_init_bool
      {
        \@@_setup_legacy_fam_two:
        \@@_setup_legacy_fam_three:
      }

    \@@_input_math_symbol_table:

%    \end{macrocode}
% \begin{itemize}
% \item the `once-off' setup that doesn't need to be per-font
% \item remap symbols that don't take their natural mathcode;
% \item activate any symbols that need to be math-active;
% \item assign delimiter codes for symbols that need to grow;
% \item setup the maths alphabets (\cs{symbf} etc.) ---
%       this is an extensive part of the code; see Section~\ref{sec:mathmap};
% \end{itemize}
%    \begin{macrocode}
    \bool_if:NT \g_@@_init_bool \@@_onceoff_setup:
    \@@_remap_symbols:
    \@@_setup_mathactives:
    \@@_setup_delcodes:
    \@@_setup_alphabets:

    %% TODO: what of the above should only be run for the "default"/"main" font?

    \bool_if:NTF \g_@@_init_bool
      {
        \bool_gset_true:N \g_@@_main_font_defined_bool
%<LU>   \@@_mathparam_store:
        \@@_log:n {default-math-font}
      }
      {
%<LU>   \@@_mathparam_restore:
      }
  }
%    \end{macrocode}
% \end{macro}
%
% \paragraph{Fall-back font}
%
% Want to load Latin Modern Math if nothing else.
% This needs to happen early so that all of the font-loading machinery executes before
% the other `AtBeginDocument' code.
%    \begin{macrocode}
\AtBeginDocument { \bool_if:NF \g_@@_main_font_defined_bool \@@_load_lm: }
\@@_cs_new:Nn \@@_load_lm:
  {
    \setmathfont{latinmodern-math.otf}[BoldFont={latinmodern-math.otf}]
  }
%    \end{macrocode}
%
% \begin{macro}{\@@_init:n}
% Reset local variables.
% Default to defining the font for every math symbol character.
%    \begin{macrocode}
\@@_cs_new:Nn \@@_init:n
  {
    \tl_set:Nn \l_@@_fontname_tl {#1}
    \bool_gset_true:N  \g_@@_ot_math_bool
    \tl_set:Nn \l_@@_mversion_tl      {normal}
    \tl_set:Nn \l_@@_symfont_label_tl {operators}

    \tl_set:Nn    \l_@@_script_features_tl  {Style=MathScript}
    \tl_set:Nn    \l_@@_sscript_features_tl {Style=MathScriptScript}
    \tl_set_eq:NN \l_@@_script_font_tl      \l_@@_fontname_tl
    \tl_set_eq:NN \l_@@_sscript_font_tl     \l_@@_fontname_tl

    \bool_gset_true:N \g_@@_init_bool
    \seq_gclear:N    \g_@@_char_range_seq
    \clist_clear:N   \l_@@_mathmap_charints_clist
    \seq_gclear:N    \g_@@_mathalph_seq
    \seq_clear:N     \l_@@_missing_alph_seq

    \cs_set_eq:NN \_@@_sym:nnn                  \@@_process_symbol_noparse:nnn
    \cs_set_eq:NN \@@_remap_symbol:nnn          \@@_remap_symbol_noparse:nnn
    \cs_set_eq:NN \@@_maybe_init_alphabet:n     \@@_init_alphabet:n
    \cs_set_eq:NN \@@_assign_delcode:nn         \@@_assign_delcode_noparse:nn
    \cs_set_eq:NN \@@_make_mathactive:nNN       \@@_make_mathactive_noparse:nNN
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_declare_math_sizes:}
% Set the math sizes according to the recommended font parameters.
%    \begin{macrocode}
\tl_new:N \g_@@_main_font_cmd_tl
\cs_new:Nn \@@_sf_size:  { \@@_fontdimen_pc_to_pt:nN {10} \g_@@_trial_font }
\cs_new:Nn \@@_ssf_size: { \@@_fontdimen_pc_to_pt:nN {11} \g_@@_trial_font }
\@@_cs_new:Nn \@@_declare_math_sizes:
  {
    \fp_gset:Nn \g_@@_size_tfsf_fp   { (\f@size + \@@_sf_size: )/2 }
    \fp_gset:Nn \g_@@_size_sfssf_fp  { (\@@_sf_size: + \@@_ssf_size:)/2 }

    \dim_compare:nF { \fontdimen 10 \g_@@_trial_font == 0pt }
      {
        \DeclareMathSizes { \f@size } { \f@size } { \@@_sf_size: } { \@@_ssf_size: }
      }
  }
%    \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\@@_fontspec_trial_font:}
%    \begin{macrocode}
\@@_cs_new:Nn \@@_fontspec_trial_font:
  {
    \tl_set:Nx \l_@@_font_keyval_tl
      {
%<LU>   Renderer = Basic,
        BoldItalicFont = {}, ItalicFont = {}, SmallCapsFont = {},
        Script = Math,
%<LU>   RawFeature = {mathfontdimen=xetex},
        \l_@@_unknown_keys_clist
      }

    \fontspec_set_family:Nxn \l_@@_trial_family_tl {\l_@@_font_keyval_tl} {\l_@@_fontname_tl}

    \group_begin:
      \fontfamily { \l_@@_trial_family_tl } \selectfont
      \exp_last_unbraced:NNo \@@_fontface_gset_eq:NN \g_@@_trial_font \font@name
      \fontspec_if_script:nF {math}
        {
          \@@_warning:n {not-ot-math}
          \bool_gset_false:N \g_@@_ot_math_bool
          \bool_gset_false:N \g_@@_init_bool
        }
    \group_end:

  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_fontspec_select_font:}
%    \begin{macrocode}
\@@_cs_new:Nn \@@_fontspec_select_font:
  {
    \tl_set:Nx \l_@@_font_keyval_tl
      {
%<LU>   Renderer = Basic,
        BoldItalicFont = {}, ItalicFont = {}, SmallCapsFont = {},
        Script = Math,
        SizeFeatures =
          {
            {
              Size = \fp_use:N \g_@@_size_tfsf_fp -
            } ,
            {
              Size = \fp_use:N \g_@@_size_sfssf_fp - \fp_use:N \g_@@_size_tfsf_fp ,
              Font = \l_@@_script_font_tl ,
              \l_@@_script_features_tl
            } ,
            {
              Size = - \fp_use:N \g_@@_size_sfssf_fp ,
              Font = \l_@@_sscript_font_tl ,
              \l_@@_sscript_features_tl
            }
          } ,
%<LU>   RawFeature = {mathfontdimen=xetex},
        \l_@@_unknown_keys_clist
      }

    \fontspec_set_family:Nxn \l_@@_family_tl {\l_@@_font_keyval_tl} {\l_@@_fontname_tl}

    \int_gincr:N \g_@@_fonts_used_int
    \group_begin:
      \fontfamily { \l_@@_family_tl } \selectfont
      \exp_last_unbraced:Nno \@@_fontface_gset_eq:cN {g_@@_mathfont_ \int_use:N \g_@@_fonts_used_int _font} \font@name
      \tl_gset:Nx \g_@@_curr_font_cmd_tl { \exp_not:c {g_@@_mathfont_ \int_use:N \g_@@_fonts_used_int _font} }
      \bool_if:NT \g_@@_init_bool
				{
					\exp_last_unbraced:NNo \@@_fontface_gset_eq:NN \l_@@_font \font@name
				}
    \group_end:
  }
%    \end{macrocode}
% \end{macro}
%
%    \begin{macrocode}
\tl_gset:Nn \g_@@_main_font_cmd_tl  { \l_@@_font }
\tl_gset:Nn \g_@@_sqrt_font_cmd_tl  { \l_@@_font }
\tl_gset:Nn \g_@@_prime_font_cmd_tl { \l_@@_font }
%    \end{macrocode}
%
% \begin{macro}{\@@_setup_math_fam:}
%    \begin{macrocode}
\@@_cs_new:Nn \@@_setup_math_fam:
  {
    \cs_if_exist:cF { sym \l_@@_symfont_label_tl }
      {
        \DeclareSymbolFont{\l_@@_symfont_label_tl}
          {\encodingdefault}{\l_@@_family_tl}{\mddefault}{\shapedefault}
      }
    \SetSymbolFont{\l_@@_symfont_label_tl}{\l_@@_mversion_tl}
      {\encodingdefault}{\l_@@_family_tl}{\mddefault}{\shapedefault}
%    \end{macrocode}
% Set the bold math version.
%    \begin{macrocode}
    \str_if_eq:eeT {\l_@@_mversion_tl} {normal}
      {
        \SetSymbolFont{\l_@@_symfont_label_tl}{bold}
          {\encodingdefault}{\l_@@_family_tl}{\bfdefault}{\shapedefault}
      }
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_setup_legacy_fam_two:}
% \TeX\ won't load the same font twice at the same scale, so we need to magnify this one by an imperceptable amount.
% Note that for extreme font sizes, this scaling value might need to be adjusted.
% 1.0001 should be enough for reasonable use cases however.
%    \begin{macrocode}
\@@_cs_new:Nn \@@_setup_legacy_fam_two:
  {
    \fontspec_set_family:Nxn \l_@@_fam_two_tl
      {
        \l_@@_font_keyval_tl,
%<LU>   RawFeature = {mathfontdimen=tex2},
%<*XE>
        ScaleAgain = 1.0001,
        FontAdjustment =
          {
            \@@_copy_fontdimen:nnN { 8} {43} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN { 9} {42} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {10} {32} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {11} {45} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {12} {44} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {13} {21} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {14} {21} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {15} {22} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {16} {18} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {17} {18} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {18} {24} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {19} {20} \g_@@_main_font_cmd_tl
            \@@_copy_fontdimen:nnN {22} {15} \g_@@_main_font_cmd_tl
            \@@_zero_fontdimen:n   {20} % delim1 = FractionDelimiterDisplaySize
            \@@_zero_fontdimen:n   {21} % delim2 = FractionDelimiterSize
         }
%</XE>
      } {\l_@@_fontname_tl}

    \SetSymbolFont{symbols}{\l_@@_mversion_tl}
      {\encodingdefault}{\l_@@_fam_two_tl}{\mddefault}{\shapedefault}

    \str_if_eq:eeT {\l_@@_mversion_tl} {normal}
      {
        \SetSymbolFont{symbols}{bold}
          {\encodingdefault}{\l_@@_fam_two_tl}{\bfdefault}{\shapedefault}
      }
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_setup_legacy_fam_three:}
% Similarly, this font is shrunk by an imperceptable amount for \TeX\ to load it again.
%    \begin{macrocode}
\@@_cs_new:Nn \@@_setup_legacy_fam_three:
  {
    \fontspec_set_family:Nxn \l_@@_fam_three_tl
      {
        \l_@@_font_keyval_tl,
%<LU>   RawFeature = {mathfontdimen=tex3},
%<*XE>
        ScaleAgain = 0.9999,
        FontAdjustment = {
          \@@_copy_fontdimen:nnN { 8} {48} \g_@@_main_font_cmd_tl
          \@@_copy_fontdimen:nnN { 9} {28} \g_@@_main_font_cmd_tl
          \@@_copy_fontdimen:nnN {10} {30} \g_@@_main_font_cmd_tl
          \@@_copy_fontdimen:nnN {11} {29} \g_@@_main_font_cmd_tl
          \@@_copy_fontdimen:nnN {12} {31} \g_@@_main_font_cmd_tl
          \@@_zero_fontdimen:n   {13}
       }
%</XE>
      } {\l_@@_fontname_tl}

    \SetSymbolFont{largesymbols}{\l_@@_mversion_tl}
      {\encodingdefault}{\l_@@_fam_three_tl}{\mddefault}{\shapedefault}

    \str_if_eq:eeT {\l_@@_mversion_tl} {normal}
      {
        \SetSymbolFont{largesymbols}{bold}
          {\encodingdefault}{\l_@@_fam_three_tl}{\bfdefault}{\shapedefault}
      }
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_onceoff_setup:}
%    \begin{macrocode}
\@@_cs_new:Nn \@@_onceoff_setup:
  {
    \@@_set_delcode:nnn {operators} {`\.} {0}
  }
%    \end{macrocode}
% \end{macro}
%
% \subsection{Functions for setting up symbols with mathcodes}
% \seclabel{mathsymbol}
%
% \begin{macro}{\@@_process_symbol_noparse:nnn}
% \begin{macro}{\@@_process_symbol_parse:nnn}
% If the \feat{range} font feature has been used, then only
% a subset of the Unicode glyphs are to be defined.
% See \secref{rangeproc} for the code that enables this.
%    \begin{macrocode}
\cs_set:Nn \@@_process_symbol_noparse:nnn
  {
    \@@_set_mathsymbol:nNNn {\l_@@_symfont_label_tl} #2 #3 {#1}
  }
%    \end{macrocode}
%    \begin{macrocode}
\cs_set:Nn \@@_process_symbol_parse:nnn
  {
    \@@_if_char_spec:nNT {#1} {#3}
      {
        \@@_process_symbol_noparse:nnn {#1} {#2} {#3}
      }
  }
%    \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@@_remap_symbols:}
% This function is used to define the mathcodes for those chars which should
% be mapped to a different glyph than themselves.
%    \begin{macrocode}
\@@_cs_new:Nn \@@_remap_symbols:
  {
    \@@_remap_symbol:nnn {`\-} {\mathbin} {"2212}
    \@@_remap_symbol:nnn {`\*} {\mathbin} {"02217}% text asterisk to "centred asterisk"
    \bool_if:NF \g_@@_literal_colon_bool
      {
        \@@_remap_symbol:nnn {`\:} {\mathrel} {"02236}% colon to ratio (i.e., punct to rel)
      }
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_remap_symbol_noparse:nnn}
% \begin{macro}{\@@_remap_symbol_parse:nnn}
% Where |\@@_remap_symbol:nnn| is defined to be one of these two, depending
% on the range setup:
%    \begin{macrocode}
\cs_new:Nn \@@_remap_symbol_parse:nnn
  {
    \@@_if_char_spec:nNT {#3} {#2}
      { \@@_remap_symbol_noparse:nnn {#1} {#2} {#3} }
  }
\cs_new:Nn \@@_remap_symbol_noparse:nnn
  {
    \clist_map_inline:nn {#1}
      { \@@_set_mathcode:nnnn {##1} {#2} {\l_@@_symfont_label_tl} {#3} }
  }
%    \end{macrocode}
% \end{macro}
% \end{macro}
%
% \subsection{Active math characters}
%
% There are more math active chars later in the subscript/superscript section.
% But they don't need to be able to be typeset directly.
%
% \begin{macro}{\@@_setup_mathactives:}
% TODO: if not an OpenType math font, we should ignore doing anything with primes.
% This needs a revamped `range` feature, I think.
%    \begin{macrocode}
\@@_cs_new:Nn \@@_setup_mathactives:
  {
		\@@_make_mathactive:nNN {"2032} \@@_prime_single_mchar \mathord
		\@@_make_mathactive:nNN {"2033} \@@_prime_double_mchar \mathord
		\@@_make_mathactive:nNN {"2034} \@@_prime_triple_mchar \mathord
		\@@_make_mathactive:nNN {"2057} \@@_prime_quad_mchar   \mathord
		\@@_make_mathactive:nNN {"2035} \@@_backprime_single_mchar \mathord
		\@@_make_mathactive:nNN {"2036} \@@_backprime_double_mchar \mathord
		\@@_make_mathactive:nNN {"2037} \@@_backprime_triple_mchar \mathord
    \@@_make_mathactive:nNN {`\'} \mathstraightquote \mathord
    \@@_make_mathactive:nNN {`\`} \mathbacktick      \mathord
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_make_mathactive:nNN}
% Makes |#1| a mathactive char, and gives cs |#2| the meaning of mathchar |#1|
% with class |#3|.
% You are responsible for giving active |#1| a particular meaning!
%    \begin{macrocode}
\cs_new:Nn \@@_make_mathactive_parse:nNN
  {
    \@@_if_char_spec:nNT {#1} #3
      { \@@_make_mathactive_noparse:nNN {#1} #2 #3 }
  }
%    \end{macrocode}
%
%    \begin{macrocode}
\cs_new:Nn \@@_make_mathactive_noparse:nNN
  {
    \@@_set_mathchar:NNnn #2 #3 {\l_@@_symfont_label_tl} {#1}
    \@@_char_gmake_mathactive:n {#1}
  }
%    \end{macrocode}
% \end{macro}
%
%
% \subsection{Delimiter codes}
%
% \begin{macro}{\@@_assign_delcode:nn}
%    \begin{macrocode}
\cs_new:Nn \@@_assign_delcode_noparse:nn
  {
    \@@_set_delcode:nnn \l_@@_symfont_label_tl {#1} {#2}
  }
%    \end{macrocode}
%
%    \begin{macrocode}
\cs_new:Nn \@@_assign_delcode_parse:nn
  {
    \@@_if_char_spec:nNT {#2} \@nil
      {
        \@@_assign_delcode_noparse:nn {#1} {#2}
      }
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_assign_delcode:n}
% Shorthand.
%    \begin{macrocode}
\cs_new:Nn \@@_assign_delcode:n { \@@_assign_delcode:nn {#1} {#1} }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_setup_delcodes:}
% Some symbols that aren't mathopen/mathclose still need to have delimiter codes assigned.
% The list of vertical arrows may be incomplete.
% On the other hand, many fonts won't support them all being stretchy.
% And some of them are probably not meant to stretch, either. But adding them here doesn't hurt.
%    \begin{macrocode}
\@@_cs_new:Nn \@@_setup_delcodes:
  {
    \@@_assign_delcode:nn {`\/}   {\g_@@_slash_delimiter_usv}
    \@@_assign_delcode:nn {"2044} {\g_@@_slash_delimiter_usv} % fracslash
    \@@_assign_delcode:nn {"2215} {\g_@@_slash_delimiter_usv} % divslash
    \@@_assign_delcode:n {"005C} % backslash
    \@@_assign_delcode:nn {`\<} {"27E8} % angle brackets with ascii notation
    \@@_assign_delcode:nn {`\>} {"27E9} % angle brackets with ascii notation
    \@@_assign_delcode:n {"2191} % up arrow
    \@@_assign_delcode:n {"2193} % down arrow
    \@@_assign_delcode:n {"2195} % updown arrow
    \@@_assign_delcode:n {"219F} % up arrow twohead
    \@@_assign_delcode:n {"21A1} % down arrow twohead
    \@@_assign_delcode:n {"21A5} % up arrow from bar
    \@@_assign_delcode:n {"21A7} % down arrow from bar
    \@@_assign_delcode:n {"21A8} % updown arrow from bar
    \@@_assign_delcode:n {"21BE} % up harpoon right
    \@@_assign_delcode:n {"21BF} % up harpoon left
    \@@_assign_delcode:n {"21C2} % down harpoon right
    \@@_assign_delcode:n {"21C3} % down harpoon left
    \@@_assign_delcode:n {"21C5} % arrows up down
    \@@_assign_delcode:n {"21F5} % arrows down up
    \@@_assign_delcode:n {"21C8} % arrows up up
    \@@_assign_delcode:n {"21CA} % arrows down down
    \@@_assign_delcode:n {"21D1} % double up arrow
    \@@_assign_delcode:n {"21D3} % double down arrow
    \@@_assign_delcode:n {"21D5} % double updown arrow
    \@@_assign_delcode:n {"21DE} % up arrow double stroke
    \@@_assign_delcode:n {"21DF} % down arrow double stroke
    \@@_assign_delcode:n {"21E1} % up arrow dashed
    \@@_assign_delcode:n {"21E3} % down arrow dashed
    \@@_assign_delcode:n {"21E7} % up white arrow
    \@@_assign_delcode:n {"21E9} % down white arrow
    \@@_assign_delcode:n {"21EA} % up white arrow from bar
    \@@_assign_delcode:n {"21F3} % updown white arrow
  }
%    \end{macrocode}
% \end{macro}
%
% \subsection{(Big) operators}
%
% The engine does what is necessary to deal with big operators for us
% automatically with \cmd\Umathchardef.
% However, the limits aren't set automatically; that is, we want to define,
% a la Plain \TeX\ \etc, |\def\int{\intop\nolimits}|, so there needs to be a
% transformation from \cmd\int\ to \cmd\intop\ during the expansion of
% \cmd\_@@_sym:nnn\ in the appropriate contexts.
%
% \begin{macro}{\l_@@_nolimits_tl}
% This macro is a sequence containing those maths operators that require a
% \cmd\nolimits\ suffix.
% This list is used when processing |unicode-math-table.tex| to define such
% commands automatically (see the macro \cs{@@_set_mathsymbol:nNNn}).
% I've chosen essentially just the operators that look like integrals;
% hopefully a better mathematician can help me out here.
% I've a feeling that it's more useful \emph{not} to include the multiple
% integrals such as $\iiiint$, but that might be a matter of preference.
%    \begin{macrocode}
\tl_set:Nn \l_@@_nolimits_tl
  {
    \int\iint\iiint\iiiint\oint\oiint\oiiint
    \intclockwise\varointclockwise\ointctrclockwise\sumint
    \intbar\intBar\fint\cirfnint\awint\rppolint
    \scpolint\npolint\pointint\sqint\intlarhk\intx
    \intcap\intcup\upint\lowint
  }
%    \end{macrocode}
% \end{macro}
%
% \subsection{Radicals}
%
% \begin{macro}{\l_@@_radicals_tl}
% The radicals are organised in \cs{@@_set_mathsymbol:nNNn}.
% We organise radicals in the same way as nolimits-operators.
% (\cs{cuberoot} and \cs{fourthroot}, don't seem to behave as proper radicals.)
%    \begin{macrocode}
\tl_set:Nn \l_@@_radicals_tl {\sqrt \longdivision \cuberoot \fourthroot}
%    \end{macrocode}
% \end{macro}
%
% \subsection{Fontdimens}
%
%    \begin{macrocode}
%<*LU>
%    \end{macrocode}
%
% \begin{macro}{\@@_mathparam_restore:}
% \cs{glb@settings} might not be necessary but is included for symmetry.
% If the maths font were to be loaded later it would clobber our mathparam settings, so
% this seems like a sensible move.
%    \begin{macrocode}
\@@_cs_new:Nn \@@_mathparam_restore:
  {
    \glb@settings
    \tl_use:N \g_@@_mathparam_settings_tl
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_mathparam_store:}
% \cs{glb@settings} is called to force maths fonts loading \emph{now} so the mathparams
% are up-to-date.
%    \begin{macrocode}
\@@_cs_new:Nn \@@_mathparam_store:
  {
    \glb@settings
    \tl_gset:Nx \g_@@_mathparam_settings_tl
      {
        \@@_mathparam_store_aux:N \displaystyle
        \@@_mathparam_store_aux:N \textstyle
        \@@_mathparam_store_aux:N \scriptstyle
        \@@_mathparam_store_aux:N \scriptscriptstyle
      }
  }
%    \end{macrocode}
%
%    \begin{macrocode}
\cs_set:Nn \@@_mathparam_store_aux:N
  {
    \Umathquad                #1 = \the \Umathquad                #1 \scan_stop:
    \Umathaxis                #1 = \the \Umathaxis                #1 \scan_stop:
    \Umathoperatorsize        #1 = \the \Umathoperatorsize        #1 \scan_stop:
    \Umathoverbarkern         #1 = \the \Umathoverbarkern         #1 \scan_stop:
    \Umathoverbarrule         #1 = \the \Umathoverbarrule         #1 \scan_stop:
    \Umathoverbarvgap         #1 = \the \Umathoverbarvgap         #1 \scan_stop:
    \Umathunderbarkern        #1 = \the \Umathunderbarkern        #1 \scan_stop:
    \Umathunderbarrule        #1 = \the \Umathunderbarrule        #1 \scan_stop:
    \Umathunderbarvgap        #1 = \the \Umathunderbarvgap        #1 \scan_stop:
    \Umathradicalkern         #1 = \the \Umathradicalkern         #1 \scan_stop:
    \Umathradicalrule         #1 = \the \Umathradicalrule         #1 \scan_stop:
    \Umathradicalvgap         #1 = \the \Umathradicalvgap         #1 \scan_stop:
    \Umathradicaldegreebefore #1 = \the \Umathradicaldegreebefore #1 \scan_stop:
    \Umathradicaldegreeafter  #1 = \the \Umathradicaldegreeafter  #1 \scan_stop:
    \Umathradicaldegreeraise  #1 = \the \Umathradicaldegreeraise  #1 \scan_stop:
    \Umathstackvgap           #1 = \the \Umathstackvgap           #1 \scan_stop:
    \Umathstacknumup          #1 = \the \Umathstacknumup          #1 \scan_stop:
    \Umathstackdenomdown      #1 = \the \Umathstackdenomdown      #1 \scan_stop:
    \Umathfractionrule        #1 = \the \Umathfractionrule        #1 \scan_stop:
    \Umathfractionnumvgap     #1 = \the \Umathfractionnumvgap     #1 \scan_stop:
    \Umathfractionnumup       #1 = \the \Umathfractionnumup       #1 \scan_stop:
    \Umathfractiondenomvgap   #1 = \the \Umathfractiondenomvgap   #1 \scan_stop:
    \Umathfractiondenomdown   #1 = \the \Umathfractiondenomdown   #1 \scan_stop:
    \Umathfractiondelsize     #1 = \the \Umathfractiondelsize     #1 \scan_stop:
    \Umathlimitabovevgap      #1 = \the \Umathlimitabovevgap      #1 \scan_stop:
    \Umathlimitabovebgap      #1 = \the \Umathlimitabovebgap      #1 \scan_stop:
    \Umathlimitabovekern      #1 = \the \Umathlimitabovekern      #1 \scan_stop:
    \Umathlimitbelowvgap      #1 = \the \Umathlimitbelowvgap      #1 \scan_stop:
    \Umathlimitbelowbgap      #1 = \the \Umathlimitbelowbgap      #1 \scan_stop:
    \Umathlimitbelowkern      #1 = \the \Umathlimitbelowkern      #1 \scan_stop:
    \Umathoverdelimitervgap   #1 = \the \Umathoverdelimitervgap   #1 \scan_stop:
    \Umathoverdelimiterbgap   #1 = \the \Umathoverdelimiterbgap   #1 \scan_stop:
    \Umathunderdelimitervgap  #1 = \the \Umathunderdelimitervgap  #1 \scan_stop:
    \Umathunderdelimiterbgap  #1 = \the \Umathunderdelimiterbgap  #1 \scan_stop:
    \Umathsubshiftdrop        #1 = \the \Umathsubshiftdrop        #1 \scan_stop:
    \Umathsubshiftdown        #1 = \the \Umathsubshiftdown        #1 \scan_stop:
    \Umathsupshiftdrop        #1 = \the \Umathsupshiftdrop        #1 \scan_stop:
    \Umathsupshiftup          #1 = \the \Umathsupshiftup          #1 \scan_stop:
    \Umathsubsupshiftdown     #1 = \the \Umathsubsupshiftdown     #1 \scan_stop:
    \Umathsubtopmax           #1 = \the \Umathsubtopmax           #1 \scan_stop:
    \Umathsupbottommin        #1 = \the \Umathsupbottommin        #1 \scan_stop:
    \Umathsupsubbottommax     #1 = \the \Umathsupsubbottommax     #1 \scan_stop:
    \Umathsubsupvgap          #1 = \the \Umathsubsupvgap          #1 \scan_stop:
    \Umathspaceafterscript    #1 = \the \Umathspaceafterscript    #1 \scan_stop:
    \Umathconnectoroverlapmin #1 = \the \Umathconnectoroverlapmin #1 \scan_stop:
  }
%    \end{macrocode}
% \end{macro}
%
%    \begin{macrocode}
%</LU>
%    \end{macrocode}
%
%    \begin{macrocode}
%</package>
%    \end{macrocode}

\endinput

% /©
%
% ------------------------------------------------
% The UNICODE-MATH package  <wspr.io/unicode-math>
% ------------------------------------------------
% 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/>.
% ------------------------------------------------
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% Copyright 2010-2017  Philipp Stephani
% Copyright 2011-2017  Joseph Wright
% Copyright 2012-2015  Khaled Hosny
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% ©/