I would like to insert code in my preamble that will replace every instance of
\caption{Short. Long long long long.}
with
\caption[Short]{Short. Long long long long.}
However, I am not too familiar with LaTeX and TeX commands. Specifically, I
don't know how to extract the text before the '.' character. After that I think
a macro and \renewcommand would finish the job. Can anyone help me?
Thank you.
