Thanks for the response. Here's a more succinct example that demonstrates this issue in a different way.

#!/usr/bin/perl                                                       
+                                        
use strict;
use warnings;
use Encode qw( );

my $orig = "\xE8\xAB\x86\x0A";
utf8::encode( my $enc_once = $orig );

utf8::decode( $enc_once );
print('length after first decode= ', length($enc_once), "\n");
utf8::decode( $enc_once );
print('length after second decode= ', length($enc_once), "\n");

# do it again but don't check the intermediate length
utf8::encode( $enc_once = $orig );

utf8::decode( $enc_once );
utf8::decode( $enc_once );
print('length after second decode= ', length($enc_once), "\n");

[download]

Here's the output: 

length after first decode= 4

length after second decode= 4

length after second decode= 2

Apparently checking the length before decoding again changes the result of calling length again, which I don't understand.

In reply to Re^2: utf8::decode vs. Encode::decode with regard to the length function by Anonymous Monk
in thread utf8::decode vs. Encode::decode with regard to the length function by Anonymous Monk

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