ruby's "any?" and "all?" methods behaviour on Empty Arrays and Hashes

ruby-on-rails ruby enumeration

The method returns true if the block never returns false or nil.

So since the block never gets called, of course it never returns false or nil, thus all returns true.

The same goes for any:

The method returns true if the block ever returns a value other than false or nil.

Since the block never gets called, it never returns a value other than false or nil, thus any returns false.

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