impl Searcher

fn new<I, P>(patterns: I) -> Option<Searcher>
where
    I: IntoIterator<Item = P>,
    P: AsRef<[u8]>,

A convenience function for constructing a searcher from an iterator of things that can be converted to a &[u8].

If a searcher could not be constructed (either because of an unsupported CPU or because there are too many patterns), then None is returned.

Example

Basic usage:

use aho_corasick::{packed::{MatchKind, Searcher}, PatternID};

# fn example() -> Option<()> {
let searcher = Searcher::new(["foobar", "foo"].iter().cloned())?;
let matches: Vec<PatternID> = searcher
    .find_iter("foobar")
    .map(|mat| mat.pattern())
    .collect();
assert_eq!(vec![PatternID::ZERO], matches);
# Some(()) }
# if cfg!(all(feature = "std", any(
#     target_arch = "x86_64", target_arch = "aarch64",
# ))) {
#     example().unwrap()
# } else {
#     assert!(example().is_none());
# }

fn config() -> Config

A convenience function for calling Config::new().

This is useful for avoiding an additional import.

fn builder() -> Builder

A convenience function for calling Builder::new().

This is useful for avoiding an additional import.

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

Return the first occurrence of any of the patterns in this searcher, according to its match semantics, in the given haystack. The Match returned will include the identifier of the pattern that matched, which corresponds to the index of the pattern (starting from 0) in which it was added.

Example

Basic usage:

use aho_corasick::{packed::{MatchKind, Searcher}, PatternID};

# fn example() -> Option<()> {
let searcher = Searcher::new(["foobar", "foo"].iter().cloned())?;
let mat = searcher.find("foobar")?;
assert_eq!(PatternID::ZERO, mat.pattern());
assert_eq!(0, mat.start());
assert_eq!(6, mat.end());
# Some(()) }
# if cfg!(all(feature = "std", any(
#     target_arch = "x86_64", target_arch = "aarch64",
# ))) {
#     example().unwrap()
# } else {
#     assert!(example().is_none());
# }

fn find_in<B: AsRef<[u8]>>(&self, haystack: B, span: Span) -> Option<Match>

Return the first occurrence of any of the patterns in this searcher, according to its match semantics, in the given haystack starting from the given position.

The Match returned will include the identifier of the pattern that matched, which corresponds to the index of the pattern (starting from 0) in which it was added. The offsets in the Match will be relative to the start of haystack (and not at).

Panics

When span does not correspond to a valid range in haystack.

Example

Basic usage:

use aho_corasick::{packed::{MatchKind, Searcher}, PatternID, Span};

# fn example() -> Option<()> {
let haystack = "foofoobar";
let searcher = Searcher::new(["foobar", "foo"].iter().cloned())?;
let mat = searcher.find_in(haystack, Span::from(3..haystack.len()))?;
assert_eq!(PatternID::ZERO, mat.pattern());
assert_eq!(3, mat.start());
assert_eq!(9, mat.end());
# Some(()) }
# if cfg!(all(feature = "std", any(
#     target_arch = "x86_64", target_arch = "aarch64",
# ))) {
#     example().unwrap()
# } else {
#     assert!(example().is_none());
# }

fn find_iter<'a, 'b, B: ?Sized + AsRef<[u8]>>(&'a self, haystack: &'b B) -> FindIter<'a, 'b>

Return an iterator of non-overlapping occurrences of the patterns in this searcher, according to its match semantics, in the given haystack.

Example

Basic usage:

use aho_corasick::{packed::{MatchKind, Searcher}, PatternID};

# fn example() -> Option<()> {
let searcher = Searcher::new(["foobar", "foo"].iter().cloned())?;
let matches: Vec<PatternID> = searcher
    .find_iter("foobar fooba foofoo")
    .map(|mat| mat.pattern())
    .collect();
assert_eq!(vec![
    PatternID::must(0),
    PatternID::must(1),
    PatternID::must(1),
    PatternID::must(1),
], matches);
# Some(()) }
# if cfg!(all(feature = "std", any(
#     target_arch = "x86_64", target_arch = "aarch64",
# ))) {
#     example().unwrap()
# } else {
#     assert!(example().is_none());
# }

fn match_kind(&self) -> &MatchKind

Returns the match kind used by this packed searcher.

Examples

Basic usage:

use aho_corasick::packed::{MatchKind, Searcher};

# fn example() -> Option<()> {
let searcher = Searcher::new(["foobar", "foo"].iter().cloned())?;
// leftmost-first is the default.
assert_eq!(&MatchKind::LeftmostFirst, searcher.match_kind());
# Some(()) }
# if cfg!(all(feature = "std", any(
#     target_arch = "x86_64", target_arch = "aarch64",
# ))) {
#     example().unwrap()
# } else {
#     assert!(example().is_none());
# }

fn minimum_len(&self) -> usize

Returns the minimum length of a haystack that is required in order for packed searching to be effective.

In some cases, the underlying packed searcher may not be able to search very short haystacks. When that occurs, the implementation will defer to a slower non-packed searcher (which is still generally faster than Aho-Corasick for a small number of patterns). However, callers may want to avoid ever using the slower variant, which one can do by never passing a haystack shorter than the minimum length returned by this method.

fn memory_usage(&self) -> usize

Returns the approximate total amount of heap used by this searcher, in units of bytes.