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Postings from June 2009
Citeren Ken Williams <perlbug-followup@perl.org>:
> -----------------------------------------------------------------
> [Please enter your report here]
>
> I was surprised by the following behavior of the parser, which
> misinterprets the union() subroutine call as a SUBNAME comparison
> routine for the sort() function:
>
> ==================
> % cat c2.pl
> use strict;
> my %one = qw(a 1 b 2 c 3);
> my %two = qw(a 1 c 2 e 3);
> sub union {
> my %h;
> $h{$_}++ for @_;
> keys %h;
> }
> foreach my $k (sort union(keys(%one), keys(%two)) ) {
> print "$k\n";
> }
>
The rt ticket has some examples to improve the documentation but noone
submited a patch.
Attached is a patch that adds:
'
Warning: Care is required when sorting the list returned from a function.
If you want to sort returned by the function call: find_records(@key)
then you can use:
@contact = sort { $a cmp $b } find_records @key;
@contact = sort +find_records(@key);
@contact = sort &find_records(@key);
@contact = sort(find_records(@key));
If instead you want to sort the array @key with the comparison routine
find_records then you can use:
@contact = sort { find_records() } @key;
@contact = sort find_records(@key);
@contact = sort(find_records @key);
@contact = sort(find_records (@key));
'
Best regards,
Bram
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