This isn't terribly clear, but it has the advantage of easily being able to define new "trouble" characters: 
#assuming input is in $string
$string=join('',map( m![<>\\/]! ? "#".char($_).";" : $_, split(//, $st
+ring)));
#                      ^^^^^^^ These are trouble characters

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In reply to Re: Safer (and cleaner) way to print user-supplied text. by swiftone
in thread Safer (and cleaner) way to print user-supplied text. by Ovid

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