However, the string I get back is always flagged as "native/raw bytes".

Yes, I can confirm (code below), although only if the original string really is ASCII. Update: To be more clear: I can only confirm this in the case the original string is ASCII; otherwise the UTF-8 flag remains enabled. In the case of an ASCII string, I don't see how it not being flagged as UTF-8 causes problems? /Update

In any case, changing the UTF-8/native flag creates problems in my code later on the line.

Perhaps this is the issue we should look at - could you show an SSCCE of how a plain ASCII string without the UTF-8 flag is causing problems for you?

use warnings;
use 5.026;
use utf8;
use open qw/:std :utf8/;

while (<DATA>) {
	chomp;
	say "'$_': ", utf8::is_utf8($_)||0;
	my $y = substr $_, 2, 2;
	say "'$y': ", utf8::is_utf8($y)||0;
}

__DATA__
abcd
€bcd
ab€d

Output:

'abcd': 1
'cd': 0
'€bcd': 1
'cd': 1
'ab€d': 1
'€d': 1

In reply to Re: substr on UTF-8 strings (updated) by haukex
in thread substr on UTF-8 strings by rdiez

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