Use case for using array as ruby hash key -


ruby allows using array hash key shown below:

hash1 = {1 => "one", [2] => 'two', [3,4] => ['three', 'four']}

i not clear on common use case be. if people can share real-world scenarios useful, appreciate it.

a great example why you'd want store arrays hash keys memoizing.

this example of how array hash key useful:

def initialize(*args)   @memoizer ||= {}   return @memoizer[args] if @memoizer[args]   # args in initializer,    # create new instance future.   @memoizer[args] = some_calculation(args) end

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