This only works because you have a UTF-8 terminal, but haven't told Perl about it.
In other words, Perl is treating the UTF-8 encoded byte sequence in the source code - which represents the Unicode char U+00F1 (ñ) - as two separate bytes, and passes them on as is (i.e. UTF-8 encoded) to the terminal, which consequently displays the character correctly.
Perl internally, however, you don't have a character string, so you cannot properly match, etc.:
#!/usr/local/bin/perl -l
use strict;
use warnings;
use Encode;
my $bytes = 'ñ'; # UTF-8 encoded source (c3 b1 = ñ)
# displays as two latin1 chars here (c3 = Ã, b1 =
+ ±),
# because PM doesn't handle UTF-8
my $chars = decode('UTF-8', $bytes);
print '$bytes eq \x{f1} ? ', $bytes eq "\x{f1}" ? "match":"no match";
print '$chars eq \x{f1} ? ', $chars eq "\x{f1}" ? "match":"no match";
print '$bytes: ', $bytes;
print '$chars: ', $chars;
binmode STDOUT, "utf8";
print '$bytes (STDOUT is UTF-8): ', $bytes;
print '$chars (STDOUT is UTF-8): ', $chars;
The string comparison outputs:
$bytes eq \x{f1} ? no match
$chars eq \x{f1} ? match
and the byte/char values print as (in a UTF-8 terminal):
$bytes: ñ
$chars:
$bytes (STDOUT is UTF-8): ñ
$chars (STDOUT is UTF-8): ñ
Note that as soon as you tell Perl that your terminal is UTF-8 (with binmode), the byte string stops printing correctly, because Perl is now converting the two byte/latin1 chars c3 and b1 to the respective UTF-8 sequences c3 83 and c2 b1, which display as two separate characters...
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