「イミテーションジュエリー」→ 「模倣品」や「偽物」というネガティブな印象を持たれがち。 @MarkusMeskanen: since the item is immutable, and if you mutated it in place you could not specialise it in a very subclass. This was noticed by Khushal Bherwani who posted an case in point on X, I am equipped to copy it, Here's my GIF of it in https://share.evernote.com/note/1593c03f-b3f0-28f9-86ce-74c0830cc691