How can I combine hashes in Perl?

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Quick Answer (TL;DR)


    %hash1 = (%hash1, %hash2)

    ## or else ...

    @hash1{keys %hash2} = values %hash2;

    ## or with references ...

    $hash_ref1 = { %$hash_ref1, %$hash_ref2 };

Overview

  • Context: Perl 5.x
  • Problem: The user wishes to merge two hashes1 into a single variable

Solution

  • use the syntax above for simple variables
  • use Hash::Merge for complex nested variables

Pitfalls

See also

Footnotes

1 * (aka associative-array, aka dictionary)

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