Hello Monks,

What is the most elegant way to combine two hashes by reference? I basically want to do this:

$x = { foo => "abc" };
$x .= { bar => "def", baz => "ghi" };

# I want $x to be:
# { foo => "abc", bar => "def", baz => "ghi" }

[download]

Obviously, the concatenation operator won't have the desired effect.

And I know I can manually concatenate the two hashes, with, say:

my $temp = { bar => "def", baz => "ghi" };
foreach my $key (keys %$temp) {
    $x->{$key} = $temp->{$key};
}

[download]

Overwriting values is expected and OK in my application.

However, is there a more elegant (and time/memory efficient) solution?

The hash refs are a return from a function. I want to concatenate the return from successive calls.

Update: Thanks for the good ideas! It turns out it is cleaner for me to just pass the reference to my helper functions, and let them modify it. I was trying to avoid the extra parameter, but looks like that will be the easiest to maintain in this case.

In reply to Concatenate anonymous hash ref by wanna_code_perl

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