impl<'a> Finder<'a>

fn new<B: ?Sized + AsRef<[u8]>>(needle: &'a B) -> Finder<'a>

Create a new finder for the given needle.

fn into_owned(self) -> Finder<'static>

Convert this finder into its owned variant, such that it no longer borrows the needle.

If this is already an owned finder, then this is a no-op. Otherwise, this copies the needle.

This is only available when the alloc feature is enabled.

fn needle(&self) -> &[u8]

Returns the needle that this finder searches for.

Note that the lifetime of the needle returned is tied to the lifetime of the finder, and may be shorter than the 'a lifetime. Namely, a finder's needle can be either borrowed or owned, so the lifetime of the needle returned must necessarily be the shorter of the two.

fn find<B: AsRef<[u8]>>(&self, haystack: B) -> Option<usize>

Returns the index of the first occurrence of this needle in the given haystack.

The haystack may be any type that can be cheaply converted into a &[u8]. This includes, but is not limited to, &str and &[u8].

Complexity

This routine is guaranteed to have worst case linear time complexity with respect to both the needle and the haystack. That is, this runs in O(needle.len() + haystack.len()) time.

This routine is also guaranteed to have worst case constant space complexity.

Examples

Basic usage:

use bstr::Finder;

let haystack = "foo bar baz";
assert_eq!(Some(0), Finder::new("foo").find(haystack));
assert_eq!(Some(4), Finder::new("bar").find(haystack));
assert_eq!(None, Finder::new("quux").find(haystack));