Is likely based on what you compare it to. For example, this passes as well let array = core::array::from_fn(|i| i); assert_eq!(array, [0, 1, 2, 3, 4,

Is likely based on what you compare it to. For example, this passes as well let array = core::array::from_fn(|i| i); assert_eq!(array, [0, 1, 2, 3, 4, 5]); The magic of type inference