Can't use an undefined value as an ARRAY...

mosh has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks,

I've got this error:

Can't use an undefined value as an ARRAY reference at line ...(the foreach line...)

$self->{entries} = [];
push(@{$self->{entries}}, { a => $a, b => $b});
my $entries = '';
foreach (my $i=0; $i<scalar(@{$self->{entries}}); $i++)
{
    ...
}
[download]

What's the meaning of the mentioned error?
What might be the problem?

Mosh.

Comment on Can't use an undefined value as an ARRAY... Download Code

Replies are listed 'Best First'.
Re: Can't use an undefined value as an ARRAY... by jeffa (Bishop) on May 17, 2005 at 17:52 UTC
I'm with cog on this one. I can't make heads or tails as to what you are trying to do here. Note that use of $a and $b should be limited to sort, but that shouldn't cause the "problem" ... if there even is one. I boiled your code down and it seems ... fine? `use strict; use warnings; use Data::Dumper; my $entries = []; push(@{$entries}, { a => 1, b => undef}); foreach (my $i=0; $i<scalar(@{$entries}); $i++) { print Dumper $entries->[$i]; }` [download] Although i would rewrite the foreach loop as such: `for my $i (0 .. $#$entries) { print Dumper $entries->[$i]; }` [download] TIMTOWTDI. jeffa L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR B--B--B--B--B--B--B--B-- H---H---H---H---H---H--- (the triplet paradiddle with high-hat)	[reply] [d/l] [select]
Re: Can't use an undefined value as an ARRAY... by cog (Parson) on May 17, 2005 at 17:48 UTC
It's hard to say, because the code you provide doesn't produce an error (except for the "..." part, of course). Try limiting the code you have to a small case that still produces an error and post it again (perhaps as a reply to this one), so that we can try again. Regards, jac	[reply]
Re: Can't use an undefined value as an ARRAY... by Anonymous Monk on Oct 08, 2014 at 20:23 UTC
Changing = @{$rowref} ; to = \@{$rowref} ; worked for me ;-)	[reply]