File: m4.info,  Node: Improved exch,  Next: Improved forloop,  Up: Answers

17.1 Solution for ‘exch’
========================

The ‘exch’ macro (*note Arguments::) as presented requires clients to
double quote their arguments.  A nicer definition, which lets clients
follow the rule of thumb of one level of quoting per level of
parentheses, involves adding quotes in the definition of ‘exch’, as
follows:

     define(`exch', ``$2', `$1'')
     ⇒
     define(exch(`expansion text', `macro'))
     ⇒
     macro
     ⇒expansion text