in reply to Re: Any good ways to handle NARROW NO-BREAK SPACE characters in regex in newer versions of Perl?
in thread Any good ways to handle NARROW NO-BREAK SPACE characters in regex in newer versions of Perl?

Hmmm. Thanks. Maybe it's not the character I think it is: 

> $ perl -wMstrict -lE "qq/Screenshot-2024-02-23-at-1.05.14 AM.p
+ng/ =~ /\s/ and say 'OK' or die" 
Died at -e line 1.

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The #8239 popped in after submitting this post. It's not actually in the code.

#8239 is 202F in hex. I don't get this.

This doesn't even work: 

> $ perl -wMstrict -lE "qq/Screenshot-2024-02-23-at-1.05.14 AM.p
+ng/ =~ /\x{202F}/ and say 'OK' or die"                               
+                                                                     
+                                                                     
+                                   
Died at -e line 1.

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$PM = "Perl Monk's";
$MC = "Most Clueless Friar Abbot Bishop Pontiff Deacon Curate Priest Vicar Parson";
$nysus = $PM . ' ' . $MC;
Click here if you love Perl Monks

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Re^3: Any good ways to handle NARROW NO-BREAK SPACE characters in regex in newer versions of Perl?
by ikegami (Patriarch) on Aug 13, 2024 at 16:02 UTC

    Even though you entered a NNBSP on the command line, your program doesn't contain a NNBSP. (And I'm not referring to the appearance of  . That's due to a PerlMonks limitation.)

    By default, Perl programs are expected to be encoded using ASCII. NNBSP isn't found in the ASCII character set, so your program can't possibly include a NNBSP.

    Assuming a UTF-8 terminal, what you actually provided Perl is equivalent to "...\xE2\x80\xAF...". But a string containing a NNBSP would be "...\x{202F}...".

    You can tell Perl that the program is encoded using UTF-8 by adding use utf8;.

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      OK, thank you! I'm getting closer but still confused AF. So this returns files as desired: 

      use utf8;
my $image_name = 'Screenshot-2024-02-23-at-1.05.14\xE2\x80\xAF';
my $files = $wac->get_all_files_in_dir($dir . '/uploads', qr/$image_na
+me/);

      [download]
      But this still does not match: 
      use utf8;
my $image_name = 'Screenshot-2024-02-23-at-1.05.14\s';
my $files = $wac->get_all_files_in_dir($dir . '/uploads', qr/$image_na
+me/);

      [download]

      I'm using neovim. It shows file is also encoded as UTF-8.

      $PM = "Perl Monk's";
      $MC = "Most Clueless Friar Abbot Bishop Pontiff Deacon Curate Priest Vicar Parson";
      $nysus = $PM . ' ' . $MC;
      Click here if you love Perl Monks

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        use utf8; has no effect in that program since it's encoded using ASCII. But it doesn't hurt since ASCII is a subset of UTF-8.

        The issue is that get_all_files_in_dir is matching against the still-encoded file names.

        The second program is effectively doing 

        my $fn = "Screenshot-2024-02-23-at-1.05.14\xE2\x80\xAF";
$fn =~ /Screenshot-2024-02-23-at-1.05.14\s/

        [download]

        That will only match if U+E2 is a space character, and it isn't.

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Re^3: Any good ways to handle NARROW NO-BREAK SPACE characters in regex in newer versions of Perl?
by haukex (Archbishop) on Aug 13, 2024 at 16:00 UTC
    The #8239 popped in after submitting this post. It's not actually in the code.

    Yeah, PerlMonks does that to Unicode characters in <code> blocks - see my node here.

    In that case, I would suspect an encoding error - see ikegami's reply and my node here.

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      I copy and pasted the file name into a file and did a hex dump: 

                00 01 02 03 04 05 06 07 - 08 09 0A 0B 0C 0D 0E 0F  012345678
+9ABCDEF

00000000  53 63 72 65 65 6E 73 68 - 6F 74 2D 32 30 32 34 2D  Screensho
+t-2024-
00000010  30 32 2D 32 33 2D 61 74 - 2D 31 2E 30 35 2E 31 34  02-23-at-
+1.05.14
00000020  E2 80 AF 41 4D 2D 31 30 - 32 34 78 36 39 38 2E 70  ...AM-102
+4x698.p
00000030  6E 67 0A                                           ng.

      [download]

      E2 80 AF

      is the UTF8. I wonder if the acting of cutting and pasting is modifying the string. I'm using tmux.

      $PM = "Perl Monk's";
      $MC = "Most Clueless Friar Abbot Bishop Pontiff Deacon Curate Priest Vicar Parson";
      $nysus = $PM . ' ' . $MC;
      Click here if you love Perl Monks

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