Can anyone explain what happens when Encode::encode_utf8 does when applied to a string with the UTF-8 flag switched on ?

AFAICS it merely removes the UTF-8 flag, as the program below seems to demonstrate.

The Encode documentation says that encode(ENCODING, ..) "Encodes a string from Perl's internal form into ENCODING and returns a sequence of octets"; Now, my understanding is that Perl's internal encoding *is* UTF-8, so that when applied to a string with the UTF-8 flag on, Encode::encode_utf8 is essentially a no-op, and merely switches off the UTF-8 flag.

Am I confused ?

Steve Collyer

################# code follows ####################### 


#!/usr/bin/perl

use strict;
use warnings;

use Encode;
use charnames qw(greek);

binmode(STDOUT, ":utf8");

my $utf8_data = "<\N{alpha}\N{beta}\N{gamma}\N{delta}>";

print $utf8_data, "\n\n";

my $enc_utf8_data = Encode::encode_utf8($utf8_data);

print Encode::is_utf8($enc_utf8_data)
                ? "\$enc_utf8_data marked as UTF-8\n\n"
                : "\$enc_utf8_data not marked as UTF-8\n\n";

print Encode::is_utf8($utf8_data)
                ? "\$utf8_data marked as UTF-8\n\n"
                : "\$utf8_data not marked as UTF-8\n\n";

if ($utf8_data eq $enc_utf8_data)
{
    print "strings differ\n";
    print "utf8_data     ", unpack("H*", $utf8_data), "\n";
    print "enc_utf8_data ", unpack("H*", $enc_utf8_data), "\n";
}
else
{
    print "strings are the same\n";
    print "utf8_data     ", unpack("H*", $utf8_data), "\n";
    print "enc_utf8_data ", unpack("H*", $enc_utf8_data), "\n";
}

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In reply to What does Encode::encode_utf8 do to UTF-8 data ? by scollyer

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