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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In reply to Re: PCRE: Repeating Subpattens After Intervening Characters by xdg
in thread PCRE: Repeating Subpattens After Intervening Characters by schnarff

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