Expand description
Like memrchr
, but searches for any of three bytes instead of just one.
This returns the index corresponding to the last occurrence of needle1
,
the last occurrence of needle2
, or the last occurrence of needle3
in
haystack
(whichever occurs later), or None
if none are found. If an
index is returned, it is guaranteed to be less than usize::MAX
.
While this is operationally the same as something like
haystack.iter().rposition(|&b| b == needle1 || b == needle2 || b == needle3)
, memrchr3
will use a highly optimized routine that can be
up to an order of magnitude faster in some cases.
Example
This shows how to find the last position of any of three bytes in a byte string.
use memchr::memrchr3;
let haystack = b"the quick brown fox";
assert_eq!(memrchr3(b'k', b'q', b'e', haystack), Some(8));