Hello,

My code is sending a hash by reference to a function and adds an element to it. The problem is that the new element isn't in the hash that I sent.

my %hash = (
    'animal' => 'bear',
    'plant' => 'oak',
    'fungus' => 'truffle',
);
test(\%hash);

print join(",", keys (%hash)),"\n";

sub test {
    my ($ref) = @_;
    my %ref_hash = %{$ref};
    $ref_hash{'new'} = 'new_v';
    print join(",", keys (%ref_hash)),"\n";
}
[download]

Output:

plant,new,fungus,animal                                               
+                                                                     
+                                        
plant,animal,fungus
[download]

I want the 'new' element to be also in the new one. I think I didn't quit understand how references work.

Output I want:

plant,new,fungus,animal                                               
+                                                                     
+                                        
plant,new,fungus,animal
[download]

2018-03-22 Athanasius Added code and paragraph tags

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In reply to passing hash ref to a function by ovedpo15

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