FAQ 4.59 How do I sort a hash (optionally by value instead of key)?

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4.59: How do I sort a hash (optionally by value instead of key)?

    Internally, hashes are stored in a way that prevents you from imposing
    an order on key-value pairs. Instead, you have to sort a list of the
    keys or values:

        @keys = sort keys %hash;    # sorted by key
        @keys = sort {
                        $hash cmp $hash
                } keys %hash;       # and by value

    Here we'll do a reverse numeric sort by value, and if two keys are
    identical, sort by length of key, or if that fails, by straight ASCII
    comparison of the keys (well, possibly modified by your locale--see

        @keys = sort {
                    $hash <=> $hash
                    length($b) <=> length($a)
                          $a cmp $b
        } keys %hash;


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