OK, I'm in UTF-8 hell here. I thought that I would at least verify that I could read and write UTF-8 strings to my database, but while working on that, I discovered that I can't even get a trivial Perl program to run understandably.

Here's my test program: 

#!/usr/bin/perl -w
use strict;
use utf8;

my (
 $codepoint,
 $test_string,
 );

 binmode STDOUT, ":utf8";
 
 $codepoint = ord('我');
 print "Codepoint of character is $codepoint\n";

 $test_string = "Here's a test string with 我\n";
 print "test_string is $test_string\n";
 
 $test_string_dec = decode('utf8', $test_string);

[download]
(In my original, I had the literal Chinese character 我 where you see the big numeric constant.)

There are at least two issues here:

  1. The presence of the "use utf8" pragma: I gather from Googling that this is no longer required in current versions of Perl (I'm using 5.8.8.) But, if I leave it out, the codepoint reported by "ord" is 250, instead of 25105. Surely Perl should know that the Chinese character is Unicode?
  2. The "binmode" statement: This interacts with the "use utf8" pragma in the following ways:
    both present: correct codepoint, correct output character, no error message
    pragma present, binmode omitted: correct codepoint, correct output character, "Wide character in print" error message.
    pragma omitted, binmode present: wrong codepoint, wrong output character, no error message
    Both omitted: wrong codepoint, output shows correct Chinese char, no error message.

So, I'm really confused. What does the "use utf8" pragma actually do in Perl 5.8.8? Why do I get the correct character showing on output even when I get the "Wide character in output..." message?

--- Marais

In reply to Re: Perl/Tk: utf8 in Text widget? by Marais
in thread Perl/Tk: utf8 in Text widget? by Marais

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