On Sat, 19 Mar 2011, Cecil Westerhof wrote:

At the moment I have I my document:
{\switchtobodyfont[1.25em]\bf M}ust

{\switchtobodyfont[1.25em]\bf S}hould

{\switchtobodyfont[1.25em]\bf C}ould

{\switchtobodyfont[1.25em]\bf N}ot now

But I like to have a macro for this, so I could just do:
\Acronym{Must Should Could Not~now}

Is more readable and when I want a change (for example another color for the
first letter), this is much easier to implement. How should I implement such
a macro?

Use recursion!

\definestartstop
 [FancyFirstLetter]
 [style={\switchtobodyfont[big]\bf},
  color=red]

\def\FancyUppercase#1%
 {\dostartFancyUppercase#1\dostopFancyUppercase}

\def\dostartFancyUppercase#1#2\dostopFancyUppercase
 {\FancyFirstLetter{#1}#2}


\def\Acronym#1%
 {\dostartAcronym#1 \dostopAcronym}

\def\dostartAcronym#1 #2\dostopAcronym
 {\doifsomething{#1}
     {\FancyUppercase{#1} %space
      \dostartAcronym#2 \dostopAcronym}}