Macro fps 

macro_rules! fps {
    ($frames:expr) => { ... };
}

Builds a FrameRate of whole frames per second from an integer constant.

A zero value fails compilation. Use FrameRate::try_new for runtime values.

use motion_core::{FrameRate, fps};
assert_eq!(fps!(30), FrameRate::try_new(60, 2).unwrap());