Re^6: Why is "any" slow in this case?

I can't follow, since you are using the /g modifier, each iteration will only capture 2 groups and then continue where it left of

/g in list context consumes till the end of string; iterating with "while" is infinite loop (all but two captures are thrown away each time), or did I misunderstood completely? OK, nevermind

Comment on Re^6: Why is "any" slow in this case? Download Code

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Re^7: Why is "any" slow in this case? by LanX (Saint) on Jul 30, 2025 at 21:41 UTC
> (all but two captures are thrown away each time) you are right I misremembered the /g, /c, pos(), \G mechanisms which only work in scalar context. Mea Culpa. But you can grep all @matches and post process them in pairs, like `use v5.14; use warnings; say "INPUT: ",my $str = join " ", 11 .. 19; my @matches = $str =~ m/(\d+) (\d+)/g ; while (my ($c,$r) = splice @matches,0,2) { say "$c - $r"; }` [download] `INPUT: 11 12 13 14 15 16 17 18 19 11 - 12 13 - 14 15 - 16 17 - 18` [download] If you want only two capture per string you can also use `/gc` to avoid an infinite loop. `use v5.14; use warnings; say "INPUT: ",my $str = join " ", 1..9; my $stop=5; while ( my ($c,$r) = ($str =~ m/(\d+) (\d)/gc) ) { say "$c $r"; die unless $stop--; }` [download] `INPUT: 1 2 3 4 5 6 7 8 9 1 2` [download] Cheers Rolf _{(addicted to the Perl Programming Language :) see Wikisyntax for the Monastery}	[reply] [d/l] [select]

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Re^7: Why is "any" slow in this case?
by LanX (Saint) on Jul 30, 2025 at 21:41 UTC

> (all but two captures are thrown away each time)

you are right I misremembered the /g, /c, pos(), \G mechanisms which only work in scalar context. Mea Culpa.

But you can grep all @matches and post process them in pairs, like

use v5.14;
use warnings;

say "INPUT: ",my $str = join " ", 11 .. 19;


my @matches = $str =~ m/(\d+) (\d+)/g ;

while (my ($c,$r) = splice @matches,0,2) {
  say "$c - $r";
}
[download]

INPUT: 11 12 13 14 15 16 17 18 19 11 - 12 13 - 14 15 - 16 17 - 18
[download]

If you want only two capture per string you can also use /gc to avoid an infinite loop.

use v5.14;
use warnings;

say "INPUT: ",my $str = join " ", 1..9;

my $stop=5;
while ( my ($c,$r) = ($str =~ m/(\d+) (\d)/gc) ) {
  say "$c $r";
  die unless $stop--;
}
[download]

INPUT: 1 2 3 4 5 6 7 8 9 1 2
[download]

Cheers Rolf
_{(addicted to the Perl Programming Language :)

see Wikisyntax for the Monastery}

[reply]
[d/l]
[select]