How to iterate over all byte values (overflowing_literals in `0..256`)

Question

I\'m trying to iterate over all possible byte (u8) values. Unfortunately my range literals in 0..256 are cast to u8 and 256

Answer 1

As of Rust 1.26, inclusive ranges are stabilized using the syntax ..=, so you can write this as:

for byte in 0..=255 {
    foo(byte);
}

Answer 2

This is issue Unable to create a range with max value.

The gist of it is that byte is inferred to be u8, and therefore 0..256 is represented as a Range<u8> but unfortunately 256 overflows as an u8.

The current work-around is to use a larger integral type and cast to u8 later on since 256 is actually never reached.

There is a RFC for inclusive range with ... which has entered final comment period; maybe in the future it'll be possible to have for byte in 0...255 or its alternative (0..255).inclusive().