I need to parse some streams of unicode text. I'd like to use Parse::RecDescent. My specific problem is I am having trouble getting Parse::RecDescent to accept characters in the form '\N{...}'. Here's an example: 
use strict;
use charnames ':full';
use Parse::RecDescent;
$::RD_TRACE = 1;
$::RD_HINT = 1;

my $parser = new Parse::RecDescent(<<'EOG') || die;
 ex1: "\N{DIAMOND OPERATOR}" {warn 'got it'} # fails despite 'use char
+names'
 ex2: "\x{22c4}" {warn 'got it'} # always works
 ex3: /\p{Letter}/ {warn 'got letter'} # fails unless 'use charnames..
+.'
EOG

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The hint offered by the parser states 'Constant(\N{...}): $^H{charnames} is not defined'.

It's interesting to note that the line 'ex3' fails if charnames isn't used, so P::RD seems to sort-of know about about charnames.

Alternatively, if anyone has dealt with unicode in P::RD grammars, I'd like to hear your opinions and experiences (hopefully not too grim).

In reply to Parse::RecDescent and unicode by cruftectomy

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