I tried to reproduce this on a later version of Perl (5.8.8) and couldn't. Here's the test I tried: 

use Test::More 'tests' => 12;

my $key = 'key';
my $encoded_key = $key;
utf8::upgrade( $encoded_key );

ok( utf8::is_utf8( $encoded_key ), 'encoded key is utf8' );
ok( ! utf8::is_utf8( $key ),       'unencoded key is not utf8' );

ok( $key eq $encoded_key,          'key eq encoded_key' );

# I don't know why these would have changed,
# but I'm checking anyway.
ok( utf8::is_utf8( $encoded_key ), 'encoded key is utf8' );
ok( ! utf8::is_utf8( $key ),       'unencoded key is not utf8' );

is( $key, $encoded_key,            'key is encoded_key' );

ok( utf8::is_utf8( $encoded_key ), 'encoded key is utf8' );
ok( ! utf8::is_utf8( $key ),       'unencoded key is not utf8' );

my %via_var  = ( $key  => 'value' );
my %hardcode = ( 'key' => 'value' );

is( $via_var{$key},          'value',
    'Can access hash via $key' );
is( $via_var{$encoded_key},  'value',
    'Can access hash via $encoded_key' );
is( $hardcode{$key},         'value',
    'Can access hardcoded hash via $key' );
is( $hardcode{$encoded_key}, 'value',
    'Can access hardcoded hash via $encoded_key' );

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I wonder if there's some difference between the version you have and the version I have, so I wonder if that test does the same thing for you that it does for me. I get the same results regardless of whether I have use utf8 at the top.

In reply to Re: hard-coded hash return nothing for utf-8 string by kyle
in thread hard-coded hash return nothing for utf-8 string by vic

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