in reply to Re^3: Parser Performance Question (updated)
in thread Parser Performance Question

The last two are still incorrect, as q< \\" > will be parsed as an escaped quote. /" (?: [^"\\] | \\. )* "/sx is the bestest solution :-P

Edit: except when I'm an idiot and confuse (?= for (?:

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Re^5: Parser Performance Question (updated)
by LanX (Saint) on Oct 06, 2017 at 02:08 UTC
    > q< \\" > will be parsed as an escaped quote

    I don't understand, it IS an escaped quote and it works for me:

      DB<175> $re = qr/ " (?: \\\\ | \\" | [^"] )* " /x;

  DB<176> p $a= q<x  "..\\".."  x>
x  "..\".."  x

  DB<177> $a =~ /$re/; print $&
"..\".."

    [download]

    update

    maybe you should show us how you'd escape a double-quote.

    Cheers Rolf
    (addicted to the Perl Programming Language and ☆☆☆☆ :)
    Je suis Charlie!

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      Meh, this will teach me about posting when I can't test. I meant q< \\\\" >; but thought the \ wouldn't escape the next one. The case where the \ just before the " is litteral because escaped, so it can't escape the ".

      use v5.20;
use Data::Dump qw( pp );
my $str = <<STR;
 " .. \\\\" .. "
STR

print $str;

my %re = (LanX => qr/ " (?: \\\\ | \\" | [^"] )* " /x,
          Eily => qr/ " (?: [^\\] | \\. )* " /x);

$str =~ /$re{$_}/ and say "$_ found $&" for keys %re;

      [download]
       " .. \\" .. "
Eily found " .. \\" .. "
LanX found " .. \\"

      [download]

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        > 
        " .. \\" .. " 
Eily found " .. \\" .. " 
LanX found " .. \\"

        [download]

        Well, you proved that my version is correct and yours doesn't work.

        :p

        Cheers Rolf
        (addicted to the Perl Programming Language and ☆☆☆☆ :)
        Je suis Charlie!

[reply]
[d/l]

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