in reply to Pattern Matching, left-to-right

Untested: 
$string =~ s/(\\(?:[FSTRE]\\)+)/
  my $x = $1;
  $x =~ tr#FSTRE\\#|^&-\\#d;
  $x;
/ge;

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-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

update: Ooops... I saw the \T\F\S\ in the source string, and figured that this was supposed to translate to &^|, when in fact the example says it translates to &F|. Ignore me. Other answers are better.

In Section Seekers of Perl Wisdom