can 'warn' but not 'print' wide character

hbm has asked for the wisdom of the Perl Monks concerning the following question:

I'm intrigued by the different results below:

perl -e 'print "\x{01C1}\n";'
Wide character in print at -e line 1.
Į

perl -e 'warn "\x{01C1}\n";'
Į

perl -e 'die "\x{01C1}\n";'
Į

perl -e 'print STDERR "\x{01C1}\n";'
Wide character in print at -e line 1.
Į
[download]

I would have thought 'warn' and 'die' did essentially 'print' to STDERR...

Comment on can 'warn' but not 'print' wide character Download Code

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Re: can 'warn' but not 'print' wide character by ikegami (Patriarch) on Sep 13, 2010 at 20:28 UTC
Maybe it was thought that warning about a warning would just add confusion? Or maybe it was just overlooked. I would have thought 'warn' and 'die' did essentially 'print' to STDERR... It does use `STDERR`, but the `print` opcode is not involved.	[reply] [d/l] [select]
Re: can 'warn' but not 'print' wide character by Khen1950fx (Canon) on Sep 13, 2010 at 23:36 UTC
I took a slightly different path. Maybe you were looking for something like this? `#!/usr/bin/perl use strict; use warnings; binmode STDERR, ':encoding(utf8)'; print STDERR "\x{01b1}\n"; binmode STDOUT, ':encoding(utf8)'; print "\x{01b1}", "\n"; warn "\x{01b1}", "\n"; die "\x{01b1}", "\n";` [download]	[reply] [d/l]
Re: can 'warn' but not 'print' wide character by Anonymous Monk on Sep 13, 2010 at 20:02 UTC
I would have thought 'warn' and 'die' did essentially 'print' to STDERR... Yes, essentially, but no, they don't call print	[reply]
Re: can 'warn' but not 'print' wide character by ikegami (Patriarch) on Sep 16, 2010 at 13:36 UTC
Turns out there was an outstanding ticket for this, and it just got resolved.	[reply]
Re^2: can 'warn' but not 'print' wide character by hbm (Hermit) on Sep 16, 2010 at 17:14 UTC
What timing! Are you in on that bug system? I believe 'die' needs the same fix. This code from the bug report: `perl -we '$a="\xee\n"; print STDERR $a; warn $a; utf8::upgrade($a); pr +int STDERR $a; warn $a'` [download] gives the same results as this: `perl -we '$a="\xee\n"; print STDERR $a; die $a;' perl -we '$a="\xee\n"; utf8::upgrade($a); print STDERR $a; die $a'` [download] Thanks!	[reply] [d/l] [select]
Re^3: can 'warn' but not 'print' wide character by ikegami (Patriarch) on Sep 17, 2010 at 18:19 UTC
I don't know if it was fixed by the same patches or by different patches, but die() will warn too in 5.14. `$ ./perl -v This is perl 5, version 13, subversion 4 (v5.13.4-312-g6e4e365) built +for i686-linux ... $ ./perl -e'warn chr 300' Wide character in warn at -e line 1. Ĭ at -e line 1. $ ./perl -e'die chr 300' Wide character in die at -e line 1. Ĭ at -e line 1.` [download]	[reply] [d/l]