I want to have a command that by default uses a default string and if supplied the optional parameter. I tried it using let, but that gives strange results
\documentclass{minimal}
\newcommand{\standardstring}{standard}
\newcommand{\printresult}[1][\standardstring]{%
\let\printstring#1
\printstring
}
\begin{document}
\printresult
\printresult[abc]
\end{document}
This results in
standard
bc a
\standardstring
has a fixed value for the whole LaTeX run? – egreg Jan 19 '14 at 15:11