utf8 bloody chars

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

Also new in perl. I'm following "Learning Perl" from O'Reilly and want to print greek letters. Here's what I do:

use 5.010;
use utf8;
$pi_char = chr(OxO3c9);
print "Greek letter here $pi_char\n";
[download]

However, in the output I get:

Greek letter here
[download]

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Re: utf8 bloody chars by bitingduck (Chaplain) on Oct 18, 2015 at 00:14 UTC
Be careful about zeros vs. the letter "O". If I put zeros where you have "O"s I get a lower case omega. It's sometimes hard to tell when reading, but the letter tends to be a bit rounder and the number more ovalized. Back in the day publishers were better about using zeros with slashes through them- I don't recall if O'Reilly has moved away from that.	[reply]
Re^2: utf8 bloody chars by thorvald (Initiate) on Oct 18, 2015 at 05:26 UTC
Thanks so much to both of you. I had never use utf before, since I have only done numerics so far	[reply]
Re: utf8 bloody chars by AnomalousMonk (Archbishop) on Oct 18, 2015 at 00:16 UTC
Especially if you are a beginner, you should place the statements `use warnings;` and `use strict;` at the beginning of all your code: `c:\@Work\Perl\monks>perl -le "use warnings; use strict; ;; use utf8; ;; my $pi_char = chr(OxO3c9); print qq{Greek letter '$pi_char' here}; " Bareword "OxO3c9" not allowed while "strict subs" in use at -e line 1. Execution of -e aborted due to compilation errors.` [download] I.e., `"OxO3c9"` (letter "O" vice decimal digit "0") is not a hex number, as already noted. See warnings and strict. In other words, "Help Perl to help you." Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re: utf8 bloody chars by shmem (Chancellor) on Oct 18, 2015 at 10:00 UTC
To interpolate unicode chars into strings you can use also `print "Greek letter here \x{03c9}\n"; print "Greek letter here \N{U+03c9}\n"; print "Greek letter here \N{GREEK SMALL LETTER OMEGA}\n";` [download] as stated in perlunicode. If you get the warning `Wide character in print`, use the -C command line switch at least as `-CO` (that's an 'oh', not a zero :-). See perlrun. You can find official unicode character names at decodeunicode. perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'	[reply] [d/l] [select]
Re^2: utf8 bloody chars by AppleFritter (Vicar) on Oct 18, 2015 at 10:11 UTC
You can find official unicode character names at decodeunicode. I've also found McLean's Unicode Character Finder very helpful when looking for specific characters.	[reply]
Re^2: utf8 bloody chars by moritz (Cardinal) on Oct 20, 2015 at 10:33 UTC
use the -C command line switch Or `binmode STDOUT, ':encoding(UTF-8)';` inside the script. Perl 6 - the future is here, just unevenly distributed	[reply] [d/l]
Re: utf8 bloody chars by Tux (Canon) on Oct 18, 2015 at 13:51 UTC
Another remark: the `use utf8;` is only required if the source code contains literal utf-8: $ perl -CO -wE'say "\x{03c9}"' ω $ perl -CO -wE'say "ω"' Ī $ perl -CO -Mutf8 -wE'say "ω"' ω Enjoy, Have FUN! H.Merijn	[reply] [d/l]

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