Changing all single quotes to be straight when within texttt

Question

I have a document with many ' characters inside of texttt. Is there a way to make them all appear straight when in texttt?

I know that I can search/replace all ' with \textquotesingle:

• Adding straight quote marks to \texttt
• Straight quotes?
• Typesetting single quotes

Perhaps there is some preamble declaration to tell texttt to render all ' as \textquotesingle?

Answer 1

Here I redefine \texttt to make ' active and replace itself with \textquotesingle. The original definition is saved in \svtexttt.

EDITED to return ' to non-active status at the conclusion of a \texttt.

REEDITED to use letltxmacro, per egreg's suggestion.

REREEDITED to restore the originally defined ' after \texttt usage, so as not to interfere with math conversion to \prime (hat tip/mumbled curse to David).

\documentclass{article}
\usepackage{textcomp,lmodern,letltxmacro}
\LetLtxMacro{\svtexttt}{\texttt}
\catcode`'=\active %
\let\svprime'
\renewcommand\texttt{\catcode`'=\active \def'{\textquotesingle}\textttaux}
\newcommand\textttaux[1]{\svtexttt{#1}\gdef'{\svprime}\catcode`'=12 }
\catcode`'=12 %
\begin{document}
\svtexttt{That's life!}

versus

\texttt{That's life!}

Is ' active? No. 

Testing prime: $x' =dx/dt$
\end{document}

Answer 2

You could make ' active, but this has the big disadvantage that \texttt can no longer be used in the argument to another command.

\documentclass{article}
\usepackage{textcomp}
\usepackage{xparse}
\usepackage{etoolbox} % for robustify

\robustify\texttt

\let\originaltexttt\texttt
\newcommand\activatestraightquote{%
  \begingroup\lccode`~=`'
  \lowercase{\endgroup\let~}\textquotesingle
  \catcode`'=\active
}
\renewrobustcmd{\texttt}{%
  \begingroup\activatestraightquote
  \innertexttt
}
\newcommand{\innertexttt}[1]{\originaltexttt{#1}\endgroup}

\begin{document}

abc'def \texttt{abc'def} abc'def

\end{document}

A solution that's free from this problem.

\documentclass{article}
\usepackage{xparse}
\usepackage{textcomp}

\ExplSyntaxOn
\RenewDocumentCommand{\texttt}{m}
 {
  \group_begin:
  \tl_set:Nn \l_jmlarson_texttt_tl { #1 }
  \regex_replace_all:nnN { ' } { \c{textquotesingle} } \l_jmlarson_texttt_tl
  \ttfamily
  \tl_use:N \l_jmlarson_texttt_tl
  \group_end:
 }
\ExplSyntaxOff


\begin{document}

\section{abc'def \texttt{abc'def} abc'def}

abc'def \texttt{abc'def} abc'def

\end{document}

This can also be extended so as to treat also " and ''.

Answer 3

You can use package newtxtt with option straightquotes.

\documentclass{article}
\usepackage[straightquotes]{newtxtt}

\begin{document}

\section{abc'def \texttt{abc'def} abc'def}

abc'def \texttt{abc'def} abc'def

\texttt{`xyz', ``xyz'', "xyz"}

\end{document}

This method, by essence, replaces completely the typewriter font, naturally. In the example above it seems to fit not so bad with default serif font.

Answer 4

Here is an approach using active characters, but still allowing \texttt usage inside arguments of other macros. (because it uses \scantokens).

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage{upquote}
\usepackage{etoolbox} % for robustify

\robustify{\texttt}
\let\originaltexttt\texttt

\begingroup
\catcode`'=\active
\catcode``=\active
\globaldefs1
\makeatletter
\renewrobustcmd{\texttt}[1]{%
   {%
   \everyeof{\noexpand}\endlinechar-1
   \expandafter\catcode\string``=\active
   \expandafter\catcode\string`'=\active
   \let'\textquotesingle
   \let`\textasciigrave
   \ifx\encodingdefault\upquote@OTone
    \ifx\ttdefault\upquote@cmtt
     \def'{\char13 }\def`{\char18 }%
    \fi
   \fi
   \scantokens{\originaltexttt{#1}}%
   }%
}%
\endgroup


\begin{document}

\null\vfill
abc'def---\texttt{abc'def}---abc'def 
\footnote{\texttt{This is a footnote ``''}}

\textit{\texttt{abc`def'ghi}}---\texttt{\textit{abc`def'ghi}}
\footnote{\textit{\texttt{This is another footnote ``''}}}

\end{document}

The advantage compared to my other answer is that it makes do with the document typewriter font, it does not modify it. The disadvantage is that \scantokens may reserve some surprises. Concretely the main issue coming to my mind is that one should not use it in a context where the space character has been made active, and the main case will be the alltt environment (of course verbatim is no issue, as \texttt macro does not get executed). But that's already a bit specialized context, so generally speaking it will be fine.

Notice that my approach loads package upquote so verbatim environment will be with straight single quotes too.

Answer 5

Here's a solution that works with both LuaLaTeX and XeLaTeX. Do examine the code below the screenshot: you'll notice that absolutely nothing needs to be done to achieve the desired outcome. This is because LuaLaTeX and XeLaTeX use "straight" apostrophes (single quotes) automatically if a monospaced font is in use (as is the case with \texttt). This is true regardless of whether or not the fontspec package is loaded.

% !TEX TS-program = lualatex   %% or xelatex
\documentclass{article}
\begin{document}
\section{abc'def \texttt{abc'def} abc'def}

abc'def \texttt {abc'def} abc'def
\end{document}