in reply to PCRE: Repeating Subpattens After Intervening Characters

merlyn's on-target comment aside, I'd normally do that by assigning the repeated pattern to a variable and interpolating that into the regex pattern. 

# original: my $pat = "\d\s+foo";
# fixed:
my $pat = "\\d\\s+foo";

my $regex = qr/$pat[^\r\n]*$pat/;

[download]

Not sure about PCRE, but whatever programming language you use, I suspect you can construct a string using variables similarly to build up to your pattern.

Update: Doh! Thanks, ikegami. I was trying to show the subpattern with strings for the cross-language analogy and slipped up.

-xdg

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Re^2: PCRE: Repeating Subpattens After Intervening Characters
by ikegami (Patriarch) on Sep 14, 2005 at 22:18 UTC
    That should be 
    my $pat = "\\d\\s+foo";

    [download]
    or better yet 
    my $pat = qr/\d\s+foo/;

    [download]

    Your pat incorrectly matches "dssssfoo", and doesn't match "1 foo" as it should.

    my $pat = "\d\s+foo";
print("$pat\n"); # ds+foo

    [download]
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Re^2: PCRE: Repeating Subpattens After Intervening Characters
by schnarff (Acolyte) on Sep 14, 2005 at 22:09 UTC
    Wow, you guys are amazingly quick to reply and helpful in those replies. That said, since I need to do this outside of Perl, in a pure PCRE expression, neither this nor ikegami's post is helpful.

    Seeing as how I just looked and found no PCREmonks, however, does anyone know if such a forum actually exists and I'm just bad at Googling, or if a forum with such a purpose exists under some different name/URL?

    Thanks Again,
    Alex
[reply]
      Wow, you guys are amazingly quick to reply and helpful in those replies. That said, since I need to do this outside of Perl, in a pure PCRE expression, neither this nor ikegami's post is helpful.

      I disagree. We didn't use anything Perl-specific. For example, here it is in JScript:

      var pat = "\\d\\s+foo";
var regexp = "(" + pat + ")[^\r\n]*(" + pat + ")";
var re = new RegExp(regexp);
re.exec(some_string);

      [download]

      (Untested)

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