# Using acronyms at start of sentence [duplicate]

I want it to capitalize the first letter of an expanded acronym used at the start of a sentence, like:

Application programming interfaces (APIs) are ...


I tried to define a new command \Acp for that purpose:

\usepackage[smaller,nohyperlinks]{acronym}
\acro{API}{application programming interface}
\newcommand{\Acp}[1]{\MakeUppercase\expandafter\acp{#1}}


However when I use it, it doesn't work as desired:

\Acp{API} are ...


produces

application programming interfaces (APIs) are ...


Unfortunately I can not use the glossaries package which accomplishes exactly that due to interpackate-incompatibilities.

I had a similar desire in the list of acronyms where I also wanted to capitalize all first letters. There I redefined a different command as suggested in Capitalize the first letter in acronym list:

\makeatletter
\patchcmd{\AC@@acro}{] #3}{] \MakeUppercase #3}{}{}
\patchcmd{\AC@@acro}{] #3}{] \MakeUppercase #3}{}{}
\makeatother


That works.

• What packages are you having a problem with in combination with glossaries? (I think glossaries is probably the best solution to this problem, so I am hoping that one can identify and fix the incompatibilities.) – mforbes Aug 22 '12 at 16:22
• A duplicate to this question got more attention, and has an answer that might help, which I extended: tex.stackexchange.com/a/150798/28808 – Chris H Jan 10 '14 at 9:32

If you don't mind switching to a relatively new package you could use acro. It naturally provides the command you want:

\documentclass{article}
\usepackage{acro}
\usepackage{relsize}

\acsetup{short-format=\textsmaller}

\DeclareAcronym{API}{
short = API ,
long  = application programming interface
}

\begin{document}

\Acp{API}

\printacronyms

\end{document}


Disclaimer: I am the author

Since I did not want to change from acronym, for me the simple solution was as mentioned in this answer. Simply write the full acronym in your tet and then use the \acused{API} to mark it as used. See MWE:

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[printonlyused,withpage]{acronym}

\title{Minimal Working Example}

\begin{document}
\maketitle

\section{Some Section}
Application programming interface \acused{API} (\ac{API}).

\section*{List of Acronyms}
\begin{acronym}[MWE]
\acro{API}{application programming interface}
\end{acronym}

\end{document}

• That works if you don't use withpage. Acronyms not spelled through \ac when first being used will have no page next to it in the acronym list. – johk95 Sep 5 '17 at 16:26