...or you can do some reference judo:

You can clean up a lot of the ugly with:

print "oops" unless () = delete $hash{$key};

Here's proof:

use YAML;
use Test::More tests => 3;

my %hash = map { $_ => $_ } 0 .. 3;

for my $key (0 .. 1)
{
    pass( "deleted $key" ) if () = delete $hash{$key};
}

is( keys %hash, 2, "deleted two keys" ) or warn Dump \%hash;

[download]

In reply to Re^2: Delete a zero-valued hash element by chromatic
in thread Delete a zero-valued hash element by sush

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