Perl Delete Base Key through Hash Reference

Question

my %myHash = (
    key1 => {
        test1 => 1,
        test2 => 2,
    },
    key2 => {
        test1 => 3,
        test2 => 4,
    },
);

my $myRef = $myHash{ "key". ((~~keys %myHash) + 1) } //= {
    test1 => 5,
    test2 => 6,
};    

Humor me and assume the above is actually practical. How is it I can delete this newly created key through the reference?

delete $myRef;

Obviously doesn't work

EDIT: So from zostay I have the following...

sub deleteRef {
    my ( $hash_var, $hash_ref ) = @_;

    for ( keys %$hash_var ) {
        delete $hash_var->{$_} if ($hash_var->{$_} == $hash_ref);
    }
}

Usage:

deleteRef(\%myHash, $myRef);

How's that? Still not recommended?

Answer 1

This will delete every occurrence of $myRef in %myHash:

for my $key (keys %myHash) {
    if ($myHash{$key} == $myRef) {
        delete $myHash{$key};
    }
}

You can use == to test for references using the same memory address.

I think this is a bad idea, but I am humoring you.

Answer 2

As it stands you'll have to loop through the hash looking for that ref. Or you could add th key to the data structure for future use.

Answer 3

How are you actually generating the new hash key?

It is bad form to search linearly through all hash values to find a particular reference and bypasses the simple fast access that hashes are supposed to provide.

It would make much more sense to write the equivalent of

my $myKey = "key". ((~~keys %myHash) + 1);
$myHash{$myKey} //= {
    test1 => 5,
    test2 => 6,
};

after which you could just do

delete $myHash{$myKey};

but everything hinges on what you really mean by "key". ((~~keys %myHash) + 1)