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#!perl
use strict;
use warnings;
use Test::More tests => 8;
use Syntax::Keyword::Gather;
# instructive example
my @numbers_with_two = gather {
for (1..20) {
take if /2/
}
};
ok eq_array(
[@numbers_with_two],
[2,12,20],
), 'bare take works';
# tests copied from 1.t to show they all work without $_
ok eq_array(
[gather { take for 1..10; take 99 }],
[1..10, 99],
), 'basic gather works (bare take)' ;
ok eq_array(
[gather { take for 1..10; take 99 unless gathered }],
[1..10],
), 'gathered works with bare take in boolean context (true)';
ok eq_array(
[gather { take for 1..10; pop @{+gathered} }],
[1..9]
), 'gathered allows modification of underlying data with bare take';
# some special tests
ok eq_array(
[gather { take for (undef, undef)}],
[undef, undef]
), 'undef gathers';
# as a warning: never forget to take the loop variable or you are
# taking $_ magically..
$_ = 99;
ok eq_array(
[
gather {
for my $i (1..2) {
take
}
}
],
[99, 99]
), 'takes 99 because hacker forgot to "take $i"';
# and also inside loop..
ok eq_array(
[
gather {
for my $i (1..2) {
$_ = $i *2;
take;
}
}
],
[2,4]
), 'taking manipulated $_ instead of (possibly intended $i)';
# and, rather as a question:
# not sure if this is wanted behaviour
is(
gather { take undef },
'',
'take: undef becomes ""');
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