[−][src]Trait nom::lib::std::str::pattern::Searcher

pub unsafe trait Searcher<'a> {
    fn haystack(&self) -> &'a str;

    fn next(&mut self) -> SearchStep;

    fn next_match(&mut self) -> Option<(usize, usize)> { ... }

    fn next_reject(&mut self) -> Option<(usize, usize)> { ... }
}
🔬 This is a nightly-only experimental API. (pattern)

API not fully fleshed out and ready to be stabilized

A searcher for a string pattern.

This trait provides methods for searching for non-overlapping matches of a pattern starting from the front (left) of a string.

It will be implemented by associated Searcher types of the [Pattern] trait.

The trait is marked unsafe because the indices returned by the [next()][Searcher::next] methods are required to lie on valid utf8 boundaries in the haystack. This enables consumers of this trait to slice the haystack without additional runtime checks.

Required methods

fn haystack(&self) -> &'a str

🔬 This is a nightly-only experimental API. (pattern)

API not fully fleshed out and ready to be stabilized

Getter for the underlying string to be searched in

Will always return the same [&str][str].

fn next(&mut self) -> SearchStep

🔬 This is a nightly-only experimental API. (pattern)

API not fully fleshed out and ready to be stabilized

Performs the next search step starting from the front.

  • Returns [Match(a, b)][SearchStep::Match] if haystack[a..b] matches the pattern.
  • Returns [Reject(a, b)][SearchStep::Reject] if haystack[a..b] can not match the pattern, even partially.
  • Returns [Done][SearchStep::Done] if every byte of the haystack has been visited.

The stream of [Match][SearchStep::Match] and [Reject][SearchStep::Reject] values up to a [Done][SearchStep::Done] will contain index ranges that are adjacent, non-overlapping, covering the whole haystack, and laying on utf8 boundaries.

A [Match][SearchStep::Match] result needs to contain the whole matched pattern, however [Reject][SearchStep::Reject] results may be split up into arbitrary many adjacent fragments. Both ranges may have zero length.

As an example, the pattern "aaa" and the haystack "cbaaaaab" might produce the stream [Reject(0, 1), Reject(1, 2), Match(2, 5), Reject(5, 8)]

Loading content...

Provided methods

fn next_match(&mut self) -> Option<(usize, usize)>

🔬 This is a nightly-only experimental API. (pattern)

API not fully fleshed out and ready to be stabilized

Finds the next [Match][SearchStep::Match] result. See [next()][Searcher::next].

Unlike [next()][Searcher::next], there is no guarantee that the returned ranges of this and [next_reject][Searcher::next_reject] will overlap. This will return (start_match, end_match), where start_match is the index of where the match begins, and end_match is the index after the end of the match.

fn next_reject(&mut self) -> Option<(usize, usize)>

🔬 This is a nightly-only experimental API. (pattern)

API not fully fleshed out and ready to be stabilized

Finds the next [Reject][SearchStep::Reject] result. See [next()][Searcher::next] and [next_match()][Searcher::next_match].

Unlike [next()][Searcher::next], there is no guarantee that the returned ranges of this and [next_match][Searcher::next_match] will overlap.

Loading content...

Implementors

impl<'a> Searcher<'a> for CharSearcher<'a>[src]

impl<'a, 'b> Searcher<'a> for CharSliceSearcher<'a, 'b>[src]

impl<'a, 'b> Searcher<'a> for StrSearcher<'a, 'b>[src]

impl<'a, F> Searcher<'a> for CharPredicateSearcher<'a, F> where
    F: FnMut(char) -> bool, [src]

Loading content...