%arrayValuesToKeys()

    Returns a new array for which the keys are the values of all the given
    arrays.

    Example:

        @foo = %array( one, two, three, four )
        %printValue( @foo, @self )

        @fee = %array( four, five, six, seven )
        %printValue( @fee, @self )

        @new = %arrayValuesToKeys( @foo, @fee )
        %printValue( @new, @self )

    Output:

        [foo] => (array)
        (
            [1] => (string)[one]
            [2] => (string)[two]
            [3] => (string)[three]
            [4] => (string)[four]
        )

        [fee] => (array)
        (
            [1] => (string)[four]
            [2] => (string)[five]
            [3] => (string)[six]
            [4] => (string)[seven]
        )

        [new] => (array)
        (
            [one] => (string)[one]
            [two] => (string)[two]
            [three] => (string)[three]
            [four] => (string)[four]
            [five] => (string)[five]
            [six] => (string)[six]
            [seven] => (string)[seven]
        )