How to invert long term to short term using ACRONYM list?

Question

In my text, I'd like to have in first use of \ac the result (all my text is typed using \ac or \acp):

PC (Personal Computer)

So, normally the result is opposite:

Personal Computer (PC)

How to customize it?

Answer 1

Change the definition of the macros \acfa and \@acf (EDIT: and their plural couterparts).

\documentclass{article}

\usepackage{acronym}

\makeatletter
\renewcommand*{\acfa}[1]{%
%    \texorpdfstring{\protect\@acf{#1}}{\AC@acl{#1} (#1)}}% DELETED
   \texorpdfstring{\protect\@acf{#1}}{#1\ (\AC@acl{#1})}}% NEW
\renewcommand*{\@acf}[1]{%
    \ifAC@footnote
       \acsfont{\AC@acs{#1}}%
       \footnote{\AC@placelabel{#1}\AC@acl{#1}{}}%
    \else
       \acffont{%
%           \AC@placelabel{#1}\AC@acl{#1}% DELETED
          \AC@placelabel{#1}\AC@acs{#1}% NEW
          \nolinebreak[3] %
%           \acfsfont{(\acsfont{\AC@acs{#1}})}% DELETED
          \acfsfont{(\acsfont{\AC@acl{#1}})}% NEW
        }%
     \fi
     \ifAC@starred\else\AC@logged{#1}\fi}
\renewcommand*{\acfpa}[1]{%
   \texorpdfstring{\protect\@acfp{#1}}{\AC@acsp{#1} (\AC@aclp{#1})}}
\renewcommand*{\@acfp}[1]{%
   \ifAC@footnote
      \acsfont{\AC@acsp{#1}}%
      \footnote{\AC@placelabel{#1}\AC@aclp{#1}{}}%
   \else
      \acffont{%
         \AC@placelabel{#1}\AC@acsp{#1}%
         \nolinebreak[3] %
         \acfsfont{(\acsfont{\AC@aclp{#1}})}%
         }%
   \fi
   \ifAC@starred\else\AC@logged{#1}\fi}
\makeatother

\begin{document}

Some text about the \ac{PC}~\dots

More about the \ac{PC}~\dots

\begin{acronym}
\acro{PC}{Personal Computer}
\end{acronym}

\end{document}

Answer 2

If you don't find a better solution declare a new command combining short and long forms, something like (not tested)

\newcommand{\firstac}[1]{\acl{#1} (\acs{#1})}