Re: Question about perlreref - are {n} and {n}? different?

usenet@xxxxxxxxxxxxxxx schreef:
> perlreref::QUANTIFIERS says:
>
> Quantifiers are greedy by default -- match the longest leftmost.
> Maximal Minimal Allowed range
> ------- ------- -------------
> {n,m} {n,m}? Must occur at least n times but no more than m times


The 'Must occur ... no more than m times' is not accurate.

#!/usr/bin/perl -w
use strict;

my $s = 'a'x100; # is more than 50 times

sub run {
local ($,, $\) = (' ', "\n");
my $re; ($re, $_) = @_;
s/$re/$1/;
print length, length($1);
}

run 'a{10,50}?(.*)' , $s;
run 'a{10,50}?(.*?)a', $s;
run 'a{10,50}?(.*?)' , $s;
run 'a{10,50}(.*?)' , $s;
run 'a{10,50}(.*)' , $s;

output:
90 90
89 0
90 0
50 0
50 50

--
Affijn, Ruud

"Gewoon is een tijger."
.

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