我有一个命令可以在数学模式下生成长行，并且希望它在多行环境中使用可选星号调用该命令时生成分割线。分割线的代码可以正确呈现左侧和右侧，但中间的文本会显示为空白。如果我删除双反斜杠，则丢失的文本会重新出现，但会有大量嵌入的空白。
\documentclass{article}
\usepackage{amsfonts}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{mathtools}
\usepackage{scalerel}
\usepackage{xparse} % loads expl3
%See interface3.pdf
% --------------------------------------------------------------------
% | From here to closing --- belongs in package |
% | |
\ExplSyntaxOn
\int_gzero_new:N \g_style_quant_parens_int
\int_gzero_new:N \g_style_quant_subscr_int
\int_gzero_new:N \g_style_set_subscr_int
\NewDocumentCommand{\equant}{mm}
{
\quant:nnn {\exists} {#1} {#2}
}
\NewDocumentCommand{\uquant}{mm}
{
\quant:nnn {\forall} {#1} {#2}
}
\NewDocumentCommand \setupquant {m}
{
\keys_set:nn {shmuel / quant} {#1}
}
\keys_define:nn {shmuel / quant}
{
subscript .choices:nn =
{
{
none,
stacked,
multiple
}
{
\int_gset:Nn \g_style_quant_subscr_int {\l_keys_choice_int-1}
}
},
subscript .default:n = multiple,
subscript .initial:n = none,
parentheses .choices:nn =
{
{
none,
single,
multiple
}
{
\int_gset:Nn \g_style_quant_parens_int {\l_keys_choice_int - 1}
}
},
parentheses .default:n = multiple,
parentheses .initial:n = none,
separater .tl_set:N = \g_style_quant_sep_tl,
separater .default:n = {.},
separater .initial:n = {}
}
\cs_new:Npn \quant:nnn #1 #2 #3
{
%\int_show:N \g_style_quant_parens_int
%\int_show:N \g_style_quant_subscr_int
% g_style_quant_parens_int \ \int_use:N \g_style_quant_parens_int \
% g_style_quant_subscr_int \ \int_use:N \g_style_quant_subscr_int \
\clist_set:Nn \l_tmpa_clist {#2}
\int_case:nn
{\g_style_quant_subscr_int}
{
{0}
{
% No subscript
% Set separater to ) ( quantifier or just quantifier
\int_compare:nTF {\g_style_quant_parens_int = 2}
{\tl_set:Nn \l_tmpa_tl {\right ) \left ( #1}}
{\tl_set:Nn \l_tmpa_tl {#1}}
\int_compare:nT {\g_style_quant_parens_int > 0} {\left (}
#1
\clist_use:Nn \l_tmpa_clist {\l_tmpa_tl}
\int_compare:nT {\g_style_quant_parens_int > 0} {\right )}
\g_style_quant_sep_tl #3
}
{1}
{
% Stacked subscript on single quantifier
\fp_set:Nn \l_tmpa_fp {ceil{\clist_count:N{\l_tmpa_clist} - 1} * .2 + 1}
\int_compare:nT {\g_style_quant_parens_int > 0} {\left (}
\scaleobj{\fp_to_decimal:N \l_tmpa_fp}{#1} \sb
{ \substack { \clist_use:Nn \l_tmpa_clist { \\ } } }
\int_compare:nT {\g_style_quant_parens_int > 0} {\right )}
#3
}
{2}
{
% Subscripts on separate quantifiers
\clist_map_inline:Nn
\l_tmpa_clist
{
% (quantifier \sb predicate) or quantifier \sb predicate
{
\int_compare:nT {\g_style_quant_parens_int > 0} {\left (}
\scaleobj{1.2}{#1} \sb
{##1}
\int_compare:nT {\g_style_quant_parens_int > 0} {\right )}
}
}
#3
}
}
}
\NewDocumentCommand{\set}{mos}
{
\IfBooleanTF {#3}
{
% \msg_term:n {set with star}
% \msg_term:n{{P1 #1}}
% \msg_term:n{{P2 #2}}
\bool_set_true:N \l_tmpa_bool
% \bool_show:N \l_tmpa_bool
}
{
\bool_set_false:N \l_tmpa_bool
}
\set_of:nnn {#1} {#2} {\l_tmpa_bool}
}
%\tl_new:N \g_style_set_sep_tl
%\tl_gset:Nn \g_style_set_sep_tl {\mid}
\NewDocumentCommand \setupset {m}
{
\keys_set:nn {shmuel / set} {#1}
}
\keys_define:nn {shmuel / set}
{
separater .tl_set:N = \g_style_set_sep_tl,
subscript .choices:nn =
{
{
stacked,
multiple
}
{
\int_gset:Nn \g_style_set_subscr_int {\l_keys_choice_int-1}
}
},
separater .initial:n = {\mid},
subscript .initial:n = stacked
}
\cs_new:Npn \set_of:nnn #1 #2 #3
{
\IfValueTF {#2}
{
\msg_term:n {set_of:nn \ has \ predicates \ #2}
}
{
\msg_term:n {set_of:nn \ has \ no \ predicates}
}
\clist_set:Nn \l_tmpa_clist {#2}
\msg_term:n {l_tmpa_clist \ set}
\tl_gset:Nn \g_tmpa_tl {\clist_use:Nn \l_tmpa_clist {\land}}
\msg_term:n {g_tmpa_tl \ set \ to \ \g_tmpa_tl}
\IfValueTF {#2}
{
\bool_if:nTF {#3}
{
\{
#1
\\ % Remove the \\ and TeX renders the condition, but with massive white space
right
% \msg_term:n {scalerel returns \scalerel{\g_style_set_sep_tl}{\g_tmpa_tl}}
\scalerel{\g_style_set_sep_tl}{\g_tmpa_tl}
% \tl_show:N \g_tmpa_tl
\}
}
{
\left \{
#1
\scalerel{\g_style_set_sep_tl}{\g_tmpa_tl}
\right \}
}
}
{
\left \{ #1 \right \}
}
}
\NewDocumentCommand{\seqname}{m}
{
\seqname:n {#1}
}
\cs_new:Npn \seqname:n #1
{
%code here \tl_count:n
\int_compare:nTF {\tl_count:n{#1} > 1}
{
{\mathbf{#1}}
}
{
{\bm {#1}}
}
}
\NewDocumentCommand{\intersection}{om}
{
\unint_of:nnn \bigcap {#1} {#2}
}
\NewDocumentCommand{\union}{om}
{
\unint_of:nnn \bigcup {#1} {#2}
}
\cs_new:Npn \unint_of:nnn #1 #2 #3
{
\IfValueTF {#3}
{
% \int_show:N \g_style_set_subscr_int
\clist_set:Nn \l_tmpa_clist {#2}
\int_case:nn
{\g_style_set_subscr_int}
{
{0}
{
% Stacked subscript
% \msg_term:n {\clist_count:N{\l_tmpa_clist} \ tokens \ stacked}
% \clist_show:N \l_tmpa_clist
\fp_set:Nn \l_tmpa_fp {ceil{\clist_count:N{\l_tmpa_clist} - 1} * .2 + 1}
\scaleobj{\fp_to_decimal:N \l_tmpa_fp}{#1} \sb
{\substack { \clist_use:Nn \l_tmpa_clist { \\ } }}
#3
}
{1}
{
% Subscripts comma separated
% \msg_term:n {\clist_count:N{\l_tmpa_clist} \ tokens \ comma \ separated}
% \clist_show:N \l_tmpa_clist
#1 \sb
\clist_use:Nn \l_tmpa_clist {,}
}
}
}
{
% No subscript
\msg_term:n {No subscript}
\clist_show:N \l_tmpa_clist
#1 #3
}
}
\ExplSyntaxOff
% | |
% | From opening to here --- belongs in package |
\begin{document}
\setupquant{subscript=stacked}
\[ \set{x,y,z} \]
\[ \set{x}[P(x)] \]
\[ \set{x}[{{P(x)},{Q(x)}}] \]
\begin{multline}
\set
{
{
\phi \circ \phi'^{-1}
}
}%
[
{
\equant
{
{(U,V,\phi) \in A},
{(U',V',\phi') \in A}
}
{V \cap V' \ne \emptyset}
}
]
\end{multline}
\begin{multline}
\set
{
{
\phi \circ \phi'^{-1}
}
}%
[
{
\equant
{
{(U,V,\phi) \in A},
{(U',V',\phi') \in A}
}
{V \cap V' \ne \emptyset}
}
]*
\end{multline}
\end{document}
答案1
问题原来是 \\ 和 \scalerel 改变了 \l_tmpa_tl 的值；如果我在每次使用 \\ 和 \scalerel 后重新计算它，那么我就会得到我想要的输出。