Function std::sys_common::memchr::memchr

source ·
pub fn memchr(needle: u8, haystack: &[u8]) -> Option<usize>
Expand description

A safe interface to memchr.

Returns the index corresponding to the first occurrence of needle in haystack, or None if one is not found.

memchr reduces to super-optimized machine code at around an order of magnitude faster than haystack.iter().position(|&b| b == needle). (See benchmarks.)


This shows how to find the first position of a byte in a byte string.

use memchr::memchr;

let haystack = b"the quick brown fox";
assert_eq!(memchr(b'k', haystack), Some(8));