For all my encoding needs, I use Encode. Encode concurs that "\xCC\xE5" is invalid UTF-8. 

use Encode  qw( decode FB_CROAK );

my $s_utf8 = "\xCC\xE5";
print("utf8::valid = ", utf8::valid($s_utf8)?1:0,"\n");

my $s_chars = eval { decode('UTF-8', $s_utf8, FB_CROAK) };
print("valid decode = ", defined($s_chars)?1:0,"\n");

[download]
utf8::valid = 1
valid decode = 0

[download]

I'm having problems locating where utf8::valid is implemented, so I don't know why it considers the string valid. I suspect it returns true for all strings of bytes (aka binary strings, strings with UTF8 flag off) such as $s_utf8 in my code.

In reply to Re: UTF8 Validity by ikegami
in thread UTF8 Validity by menolly

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