I just realized that when I said, "this syntax is available", people might have understood it to mean, "you can use this syntax to index arrays" (which is not t

I just realized that when I said, "this syntax is available", people might have understood it to mean, "you can use this syntax to index arrays" (which is not true for the array type defined in base). What I meant was, "you can define an array type with this indexing behavior without changing the language (since you can override the behavior of both () and [] on a particular type)".