Top-level constants in BasicObject
If you want to access top-level constants inside a BasicObject class, you need to prefix them with ::.
This will not work
class Foo < BasicObject
def bar
Hash.new
end
end
Foo.new.bar # => NameError: uninitialized constant Foo::Hash
You need to explicitly write ::Hash.
The reason is that top-level constants are internally attached to Object, so Hash is not in the lookup chain inside a BasicObject.
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