bug#1593: update

bug#1593: update

[Pietro Giorgianni]

Hi,

The %{} syntax is actually a special case of
%[<WHAT>]<DELIMITER>...<DELIMITER>, where

<WHAT>, optional, can be:
  q - single quote string, as in 'foo';
  Q - double quote string, as in "foo";
  x - command output expression, as in `foo`;
  r - regexp, as in /foo/

<DELIMITER> can by any non-alphanumeric character, including spaces
and newline, or the pairs {}, [], (), <>.

This means that things like %|"|, which is equivalent to '"' (or to
"\""), can mess up syntax highlight in emacs.

thanks again