Can't infer generic integer constants as floating-point

[ghost]

fn main() {
    let x: f64 = 2.0;
    println!("{}", x / 2);
}

Returns:

expected `f64` but found `<generic integer #0>` (expected f64 but found integral variable)

Easy fix is to change the 2 to a 2.0, although that seems kind of excessive in this case. It makes more sense to make integer constants generic numbers, like Haskell does, if they're going to be generic.

[thestinger]

Proposals to change language semantics need to go through the RFC process. There happens to be an RFC for this already:

rust-lang/rfcs#183