Using the length function to count unicode characters is a bug waiting to happen. It works with your dataset and will work with many others, but may fail on certain languages or with complex data. Much more robust is to use unicode properties.

#!/usr/bin/env perl
use warnings;
use v5.14;
binmode STDOUT, 'utf8';
binmode DATA, 'encoding(utf-8)';
 
while (<DATA>) {
    chomp;
    print $_, ': ';
    s/[A-Za-z]//g;
    my $alphacount = () = /\p{Alpha}/g;
    say "non-[A-Za-z] symbols <$_> contain $alphacount alphabetic char
+acters";
}

__DATA__
æðaber
æðahnútur
æðakölkun
æðardúnn
æðarfugl
æðarkolla
æðarkóngur
æðarvarp
æðruorð

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My standard practice has become to use utf8::all to handle all streams and save me from specifying each stream encoding separately. There's probably some pitfalls in using it but so far I haven't encountered any.

In reply to Re: length() miscounting UTF8 characters? by farang
in thread length() miscounting UTF8 characters? by Anonymous Monk

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