In my experience, tr and Unicode don't mix well. Here's my approach (source code stored in UTF-8 encoding): 
use strict;
use warnings;
use utf8;
use 5.010;
use Unicode::Normalize qw/NFKD/;
binmode STDOUT, ':encoding(UTF-8)';

sub frob {
    my $str = NFKD(shift);
    $str =~ s/\pM//g;
    $str =~ s/[^a-z-A-z0-9]/_/g;
    $str;
}

my $test = '&[]ÀÂÄàâäÇçÉÊÈËéêèëÏÌÎïìîÖÔÒöôòÜÛÙüûù?!;«»()" íóñÑáéóúÁÉÍÓ
+Ú';
say frob $test;
__END__
[]AAAaaaCcEEEEeeeeIIIiiiOOOoooUUUuuu_________ionNaeouAEIOU

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Update: Since several people misunderstood me, I feel I should clarify. I wrote that in my experience, Unicode and tr/// don't mix. Which is to say that tr/// isn't buggy, but I haven't encountered any code in the wild that correctly handles Unicode strings with tr///, because tr wasn't designed with Unicode in mind.

Perl 6 - second systems done right

In reply to Re: tr{}{} doesn't wanna work.. what am I doing wrong? by moritz
in thread tr{}{} doesn't wanna work.. what am I doing wrong? by ultranerds

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