The word borders are tricky and certainly should not be used with Unicode data, as /\b/ means a border between \W and \w, i.e. between [A-Za-z0-9] and [^A-Za-z0-9].

You must decide what you call a 'word'. In my opinion it is any alphanumeric sequence with apostrophes and hyphens, but your definition may differ. 

#!/usr/bin/perl

use warnings;
use strict;

my $test = "TEST TESt TE'st T 12TE";
while ($test =~ /(?<![\pL\pN\'-])       #NOT a hyphen, apostroph, lett
+er or number before
                 (\p{Lu}{2,})           # two or more uppercase letter
+s
                 (?![\pL\pN\'-])        #NOT a hyphen, apostroph, lett
+er or number after
                /xg) 
{  
    print "$1\n";
}

[download]
My regex matches only "TEST" at the beginning of the string in the example.
     s;;Just-me-not-h-Ni-m-P-Ni-lm-I-ar-O-Ni;;tr?IerONim-?HAcker ?d;print

In reply to Re: regular expressions in unicode by Ieronim
in thread regular expressions in unicode by Anonymous Monk

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