len

regroup

Function len 

Source 
pub fn len<T>(array: &(impl AsArrayOf<T> + ?Sized)) -> usize
Expand description

Get the number of Ts in an array of Ts.

§Panics

Panics if try_len::<T>(array) would have returned None.

§Examples

let array: [[u8; 4]; 5] = [[0; 4]; 5];
assert_eq!(regroup::len::<u8>(&array), 20);
assert_eq!(regroup::len::<[u8; 4]>(&array), 5);

let vec = vec![[0u32; 4]; 7];
let slice: &[[u32; 4]] = vec.as_slice();
assert_eq!(regroup::len::<u32>(slice), 28);
assert_eq!(regroup::len::<[u32; 4]>(slice), 7);
ⓘ
let array: [[(); usize::MAX]; 2] = [[(); usize::MAX]; 2];
let length = regroup::len::<()>(&array); // overflow
let array: [[[(); usize::MAX]; 2]; 0] = [];
let length = regroup::len::<()>(&array); // no overflow
assert_eq!(length, 0);