我想遍歷逗號分隔的清單來翻譯一些單字。我已經找到瞭如何使用包\docsvlist中的方法來做到這一點etoolbox。但是，在第一個單字之前和單字之間列印了很大的空格，而在列印的逗號之後只應該有一個「正常」空格。我認為問題出在\ifstrequal用於翻譯的命令的嵌套。
下面是一個 MWE，其中包括一個呼叫所有可能翻譯的範例和另一個僅呼叫第一個翻譯的範例，以顯示巢狀的影響。
如何避免這些額外的空間？
微量元素
\documentclass{article}
\usepackage{etoolbox}
\begin{document}
\newcommand\TranslateAnimal[1]{
\ifstrequal{#1}{Cat}{Chat}{
\ifstrequal{#1}{Dog}{Chien}{
\ifstrequal{#1}{Mouse}{Souris}{
\ifstrequal{#1}{Bird}{Oiseau}{
\ifstrequal{#1}{Horse}{Cheval}{
#1 % If there is no known translation
}}}}}
}
\newcommand{\TranslateAnimalList}[2][,]{
\def\nextitem{\def\nextitem{#1}}% Separator
\renewcommand*{\do}[1]{\nextitem\TranslateAnimal{##1}} % How to process each item
\docsvlist{#2}% Process list
}
There are additional large spaces before the first word and after words: \TranslateAnimalList{Cat,Bird,Dog,Horse,Mouse,Seal,Donkey}
Compare with: \TranslateAnimalList{Cat,Cat,Cat,Cat,Cat,Cat,Cat} where there is only a large space before the first word
\end{document}
答案1
檢查差異並查看行尾的百分號 (%) 有什麼用？ （為什麼我的巨集會創造額外的空間？）
\documentclass{article}
\usepackage{etoolbox}
\newcommand\TranslateAnimal[1]{%
\ifstrequal{#1}{Cat}{Chat}{%
\ifstrequal{#1}{Dog}{Chien}{%
\ifstrequal{#1}{Mouse}{Souris}{%
\ifstrequal{#1}{Bird}{Oiseau}{%
\ifstrequal{#1}{Horse}{Cheval}{%
#1% If there is no known translation
}}}}}%
}
\newcommand{\TranslateAnimalList}[2][, ]{%
\def\nextitem{\def\nextitem{#1}}% Separator
\renewcommand*{\do}[1]{\nextitem\TranslateAnimal{##1}}% How to process each item
\docsvlist{#2}% Process list
}
\begin{document}
The list is \TranslateAnimalList{Cat,Bird,Dog,Horse,Mouse,Seal,Donkey}.
Compare with \TranslateAnimalList{Cat,Cat,Cat,Cat,Cat,Cat,Cat}.
\end{document}
您可能會欣賞不同的實現expl3。
\documentclass{article}
%\usepackage{xparse} % not needed with LaTeX 2020-10-01 or later
\ExplSyntaxOn
\NewExpandableDocumentCommand{\TranslateAnimal}{m}
{
\str_case:nnF { #1 }
{
{Cat}{Chat}
{Dog}{Chien}
{Mouse}{Souris}
{Bird}{Oiseau}
{Horse}{Cheval}
}
{ #1 } % no known translation
}
\NewDocumentCommand{\TranslateAnimalList}{O{,~}m}
{
\seq_clear:N \l_tmpa_seq
\clist_map_inline:nn { #2 }
{
\seq_put_right:Nn \l_tmpa_seq { \TranslateAnimal { ##1 } }
}
\seq_use:Nn \l_tmpa_seq { #1 }
}
\ExplSyntaxOff
\begin{document}
The list is \TranslateAnimalList{Cat,Bird,Dog,Horse,Mouse,Seal,Donkey}.
Compare with \TranslateAnimalList{Cat,Cat,Cat,Cat,Cat,Cat,Cat}.
\end{document}
