When reassigning to an argument in a Ruby method and then calling `super` → The reassigned one is used

[^ assign]: If you just act a destructive method instead of an assignment, the original and new objects are the same, so this question is out of the question.

I didn't know, so I experimented.

class Foo
	def mtd(str)
		puts "[Foo:1] str => %p (%#08x)" % [str, str.__id__]

class Bar < Foo
	def mtd(str)
		puts "[Bar:1] str => %p (%#08x)" % [str, str.__id__]
		str *= 2
		puts "[Bar:2] str => %p (%#08x)" % [str, str.__id__]



[Bar:1] str => "abc" (0x00003c)       <--The original object passed as a formal argument
[Bar:2] str => "abcabc" (0x000050)    <--Object reassigned and overwritten (different ID)
[Foo:1] str => "abcabc" (0x000050)    <--Result: Overwritten is used

If you write only super, it complements the feeling ofsuper (str), and as a result, it is better to reassign.

Just in case, when I looked at the reference manual, it was written firmly in ** Sample Code ** .. (It is difficult because it can be interpreted in either way if it is a textual explanation)

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