vendor/regex-1.4.6/src/find_byte.rs

   1 /// Searches for the given needle in the given haystack.
   2 ///
   3 /// If the perf-literal feature is enabled, then this uses the super optimized
   4 /// memchr crate. Otherwise, it uses the naive byte-at-a-time implementation.
   5 pub fn find_byte(needle: u8, haystack: &[u8]) -> Option<usize> {
   6     #[cfg(not(feature = "perf-literal"))]
   7     fn imp(needle: u8, haystack: &[u8]) -> Option<usize> {
   8         haystack.iter().position(|&b| b == needle)
   9     }
  10
  11     #[cfg(feature = "perf-literal")]
  12     fn imp(needle: u8, haystack: &[u8]) -> Option<usize> {
  13         use memchr::memchr;
  14         memchr(needle, haystack)
  15     }
  16
  17     imp(needle, haystack)
  18 }