Make \translate'd string uppercase

Question

I'd like to typeset German weekday names in uppercase using the translator package but I can't get it working:

\documentclass[ngerman]{article}
\usepackage{babel}
\usepackage{translator}
\usedictionary{translator-months-dictionary}

\begin{document}

\translate{Monday}
\uppercase{\translate{Monday}}
\expandafter\uppercase\expandafter{\translate{Monday}}
\MakeUppercase{\translate{Monday}}
\expandafter\MakeUppercase\expandafter{\translate{Monday}}

\end{document}

The result is

Montag MONDAY MONDAY MONDAY MONDAY

How to get MONTAG?

Answer 1

This works:

   \translatelet\foo{Monday}\MakeUppercase{\foo}

or for the pgf example

{\def\translate#1{\translatelet\foo{#1}\MakeUppercase{\foo}}%
\pgfcalendarweekdayname{0}}

Answer 2

With \uppercase{\translate{Monday}} you're simply doing

\translate{MONDAY}

which results in "MONDAY" because the string isn't know. The same happens with the other tries, because \translate doesn't expand in a unique step (and is not fully expandable either).

Here's a way out: the command \translate{xyz} actually calls

\translatelet\trans@temp{xyz}\trans@temp

that is it stores the translated string into \trans@temp and then uses the string. So we can use the same mechanism and put \MakeUppercase in the proper place. I'll define \translateUC with the same syntax as \translate:

\documentclass[ngerman]{article}
\usepackage{babel}
\usepackage{translator}
\usedictionary{translator-months-dictionary}

\makeatletter
\newcommand{\translateUC}[2][]{%
  \translatelet[#1]\trans@temp{#2}%
  \MakeUppercase{\trans@temp}}
\makeatother

\begin{document}

\translate{Monday}

\translateUC{Monday}

\end{document}