2.2 Quoting input to m4

A quoted string is a sequence of characters surrounded by quote strings, defaulting to ` and ', where the nested begin and end quotes within the string are balanced. The value of a string token is the text, with one level of quotes stripped off. Thus

     `'
     =>

is the empty string, and double-quoting turns into single-quoting.

     ``quoted''
     =>`quoted'

The quote characters can be changed at any time, using the builtin macro changequote. See Changequote, for more information.