Oops, the quick-reference is wrong. The other docs correctly say that default floats are f64. Default int is i32 though. Fixing it.

My understanding is that i32 and f64 literals are pretty common among the more modern languages because f64 isn't much slower than f32 on modern CPUs and f32 costs precision, but i64 is slower than i32 (especially multiplies and divides or on 32 bit hardware) and i32 costs range, not precision, and most uses don't need the extra range.