Re: how to split the string into two or three numbers based on certain value.

If you really want a regex-solution (which isn't necessarily the best idea), here's one from the bottom of the poison cabinet:

use strict;
use warnings;
use 5.010;

$_ = '79899920179';

my $pass = qr/(?=)/;
my $fail = qr/(*FAIL)/;
while (/\G(\d{2,}?)(??{ $1 >= 32 ? $pass : $fail  })/g) {
    say $1;

}
[download]

I'm sure that can be simplified somehow, but right now I don't know how.

Be sure to read the warning about (??{...}) in perlre.

And here's a nicer Perl 6 solution:

$ perl6 -e 'say "79899920179".comb(/ (\d **? 2..*) <?{ $0 >= 32 }>/)'
79 89 99 201 79
[download]

Perl 6 - the future is here, just unevenly distributed

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Re^2: how to split the string into two or three numbers based on certain value. by AnomalousMonk (Archbishop) on Feb 11, 2013 at 23:47 UTC
A slight simplification. I'm not sure the `\G` is necessary: the given test string produces the same groups with/without it. (Update: And the same caveat about a regex solution possibly not being optimum.) See Extended Patterns in perlre. `>perl -wMstrict -le "my $s = '79899920179'; ;; my @n = $s =~ m{ \G (\d{2,3}?) (?(?{ $^N < 32 }) (*FAIL)) }xmsg; printf qq{'$_' } for @n; " '79' '89' '99' '201' '79'` [download]	[reply] [d/l] [select]
Re^3: how to split the string into two or three numbers based on certain value. by venky4289 (Novice) on Feb 12, 2013 at 08:19 UTC
Hi this works perfectly fine. Can you explain me the regulsr expression as i am nee to perl programming	[reply]
Re^4: how to split the string into two or three numbers based on certain value. by AnomalousMonk (Archbishop) on Feb 12, 2013 at 15:41 UTC
Can you explain me the regulsr expression ... I can begin to explain it and then pass you off to some explanations in the docs that do a better job than I could. `\G` Begin a 'global' search (i.e., a search controlled by the `/g` regex modifier) at the exact position where the previous search left off, or at the start of the string (same as `\A`) if there was no previous search. `(\d{2,3}?)` Capture two or three decimal digits. Because the `?` 'lazy' match modifier controls matching, try first to capture two digits (normal matching would be 'greedy' and try to grab three). `(?(?{ $^N < 32 }) (FAIL))` If the two digits captured by the immediately previous capture group (see `$^N` in perlvar) are numerically less than 32, fail that match and go back and try for three digits. Here's where I bail out. See Extended Patterns in perlre and search for the `"(?(condition)yes-pattern)"` discussion; also check the Conditional expressions section in perlretut. Check Special Backtracking Control Verbs in perlre for info on `(FAIL)`; see also the Backtracking control verbs discussion in perlretut. (Note that `(*FAIL)` can be replaced by `(?!)` if you're scared by the "WARNING: These patterns are experimental and subject to change..." language prefacing documentation of these verbs.) HTH.	[reply] [d/l] [select]