Use the crate num
Cargo.toml:
[dependencies.num]
version = "0.1.25"
default-features = false
Since you only need the crate's basics, use default-features = false.
Rust:
extern crate num;
use num::range_step;
for i in range_step(0, 10, 2) {
/* */
}
range_step is generic over rust's integer types.