Should operators on literals delay range check?

```def var : S8 = 0 - 128;```

Should it not compile, because `128` is not a valid number for the expected type `S8`? In which case, the code needs to be written as:
```def var : S8 = expect!S16(0 - 128);```

Or should the check for range be delayed? How about:

```def var : S8 = 128 - 256;```?