Changing your code to: 
perl -wle 'for (0 .. 255) { 
   $delim = chr;
   next if $delim =~ /\w/;
   eval "m${delim}foo$delim;";
   print "Bad: $_ ($delim)" if $@ 
}'

[download]
Makes '.' and ';' pass too. I also have no problem with '_'.

In reply to Re^2: Regex delimiter by lidden
in thread Regex delimiter by Outaspace

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