in reply to Re^2: UTF8 Output with XML::Feed? (use utf8)
in thread UTF8 Output with XML::Feed?

"For what it's worth, the following appears to produce only a blank line."

Please go back and (re)read the utf8 documentation; paying particular attention to the very clear and emboldened directive:

Do not use this pragma for anything else than telling Perl that your script is written in UTF-8.

The code you presented only contains 7-bit ASCII characters.

You got what appeared to be a blank line. Here are some things you could have tried: 

$ perl -e 'print "\N{LATIN SMALL LETTER A WITH RING ABOVE}\n";'
 

$ perl -e 'print "|\N{LATIN SMALL LETTER A WITH RING ABOVE}|\n";'
| |

$ perl -C -e 'print "\N{LATIN SMALL LETTER A WITH RING ABOVE}\n";'
å

$ perl -e 'use open OUT => qw{:encoding(UTF-8) :std}; print "\N{LATIN 
+SMALL LETTER A WITH RING ABOVE}\n";'
å

[download]

See: perlrun for -C; and, the open pragma.

— Ken

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Re^4: UTF8 Output with XML::Feed? (updated)
by LanX (Saint) on Mar 07, 2022 at 20:09 UTC
    > The code you presented only contains 7-bit ASCII characters.

    erm ... åäö???

    update

    > Do not use this pragma for anything else than telling Perl that your script is written in UTF-8.

    Unfortunately this line is easily misunderstood. I recently had a long dispute with a camel award winner who read it wrongly.

    Many think it only means you can use unicode characters for identifiers, like $möhre or sub née but it covers also literal strings read thru the same file-handle DATA.

    Please note how the UTF8 flag is set for $t2 (see FLAGS)

    use v5.12;
use warnings;
use Devel::Peek;


my $t1='åäö';
Dump $t1;

use utf8;

my $t2='åäö';
Dump $t2;


my $t3 = "\N{LATIN SMALL LETTER A WITH RING ABOVE}\n";
say $t3;
Dump $t3;

    [download]
    OUTPUT: 
    SV = PV(0xd9ae08) at 0x25809b0
  REFCNT = 1
  FLAGS = (POK,IsCOW,pPOK)
  PV = 0x260a4e8 "\303\245\303\244\303\266"\0
  CUR = 6
  LEN = 10
  COW_REFCNT = 1
SV = PV(0xd9add8) at 0x2580248
  REFCNT = 1
  FLAGS = (POK,IsCOW,pPOK,UTF8)
  PV = 0x260a068 "\303\245\303\244\303\266"\0 [UTF8 "\x{e5}\x{e4}\x{f6
+}"]
  CUR = 6
  LEN = 10
  COW_REFCNT = 1
SV = PV(0xd9afe8) at 0x2580a40
  REFCNT = 1
  FLAGS = (POK,IsCOW,pPOK,UTF8)
  PV = 0x2767378 "\303\245\n"\0 [UTF8 "\x{e5}\n"]
  CUR = 3
  LEN = 10
  COW_REFCNT = 1
å

    [download]

    UPDATE2

    extended the code with $t3, which doesn't print an empty line for me but å

    UPDATE3

    of course, how the print is displayed depends also on the output channel and the display settings.

    Cheers Rolf
    (addicted to the Perl Programming Language :)
    Wikisyntax for the Monastery

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      erm ... åäö???

      I had the same thought on my first reading of that post, and even send a /msg to that effect.

      But then I reread kcott's post, and saw that the second block of code from the earlier post was the code kcott focused on, and was presumably the code that kcott said didn't need use utf8; -- which seems right, because it doesn't contain non-ASCII characters.

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        yes I realized it in the meantime.

        I didn't expect it but \N{} is automatically activating the utf8 flag for the surrounding string. (which makes sense in hindsight)

        use v5.12;
use warnings;
use Devel::Peek;
#use open OUT => qw{:encoding(UTF-8) :std};


my $t4 = "\N{LATIN SMALL LETTER A WITH RING ABOVE}\n";
Dump $t4;
warn "t4: ",$t4;
__DATA__

        [download]
        OUTPUT: 
        SV = PV(0xe7ae08) at 0xd308f0
  REFCNT = 1
  FLAGS = (POK,IsCOW,pPOK,UTF8)
  PV = 0x2742188 "\303\245\n"\0 [UTF8 "\x{e5}\n"]
  CUR = 3
  LEN = 10
  COW_REFCNT = 1
t4: å

        [download]

        Cheers Rolf
        (addicted to the Perl Programming Language :)
        Wikisyntax for the Monastery

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      G'day Rolf,

      I wrote my post (to which you replied) very early this morning ... then there was $work ... now it's my lunchtime and I see your original question has been resolved (with some input from pryrt). So, there's probably little more for me to say about that specifically.

      Thanks for all of the extra work you did: Devel::Peek and so on.

      By the way, I got a huge laugh from your latest user image. Thanks for that also.

      — Ken

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