Doozer:

If the item doesn't exist, you're just going to create it anyway, so why not just use:

push @{$hash{A1}{B2}{C1}}, $item;

[download]

Without showing more of your code, we can't be sure exactly what your problem is. I'm suspecting that it's due to the fact that sometimes your B-level variable is a string and sometimes it's a hash reference. Perhaps $hash{A1}{B2} was a string a moment before executing the code you've shown--that would be enough to cause the problem:

$ perl ttt3.pl
Can't use string ("") as a HASH ref while "strict refs" in use at ttt3
+.pl line 7.
* /W/P/PM/ monitor_saints;  check TODO_LIST

$ cat ttt3.pl
#!/usr/bin/perl
use strict; use warnings;
use Data::Dumper;

my %hash;
$hash{A1}{B2} = "";
if (exists $hash{A1}{B2}{C1}) {
    print "Baz!\n";
}

[download]

...roboticus

When your only tool is a hammer, all problems look like your thumb.

In reply to Re: How to add to hash of a hash of an array. Confused.com! by roboticus
in thread How to add to hash of a hash of an array. Confused.com! by Doozer

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