macro_rules! array_ref {($slice:expr, $offset:expr, $len:expr) => {::arrayref::array_ref!($slice, $offset, $len)// the current macro};($slice:tt[$from:tt..$to:expr]) => {
array_ref!($slice, $from, $to - $from)};($slice:tt[..$to:expr]) => {
array_ref!($slice,0, $to)};($slice:tt[$from:tt..=$to:expr]) => {
array_ref!($slice, $from, $to - $from + 1)};}#[cfg(test)]mod tests {use hex_literal::hex;#[test]fnfrom_zero_len_2(){let bytes:&[u8] = &hex!("01 02 03");let a = array_ref!(bytes,0,2);let b = array_ref!(bytes[..2]);let c = array_ref!(bytes[0..2]);let d = array_ref!(bytes[0..=1]);assert_eq!(a, b);assert_eq!(a, c);assert_eq!(a, d);assert_eq!(vec![1,2], a.to_vec());}#[test]fnfrom_one_len_2(){let bytes:&[u8] = &hex!("01 02 03");let a = array_ref!(bytes,1,2);let b = array_ref!(bytes[1..3]);let c = array_ref!(bytes[1..=2]);assert_eq!(a, b);assert_eq!(a, c);assert_eq!(vec![2,3], a.to_vec());}#[test]fnfrom_two_len_1(){let bytes:&[u8] = &hex!("07 08 09");let a = array_ref!(bytes,2,1);let b = array_ref!(bytes[2..3]);let c = array_ref!(bytes[2..=2]);assert_eq!(a, b);assert_eq!(a, c);assert_eq!(vec![9], a.to_vec());}#[test]#[allow(clippy::many_single_char_names)]fnexpressions_and_non_literals(){let bytes:&[u8] = &hex!("05 06 07 08");let a = array_ref!(bytes,2,1 + 1);let b = array_ref!((bytes[2..])[..1 + 1]);let c = array_ref!(bytes[2..1 + 3]);let d = array_ref!(bytes[2..=2 + 1]);constSTART:usize = 1 + 1;constEND:usize = 1 + 2;let e = array_ref!(bytes[START..=END]);assert_eq!(a, b);assert_eq!(a, c);assert_eq!(a, d);assert_eq!(a, e);assert_eq!(vec![7,8], a.to_vec());}}
I wonder if you would be open to a PR that allowed for most slice syntax, or have any thoughts on whether this is a good or bad idea.
A typical usage, calling a method that needs an array:
Implementation