Trait std::str::pattern::Searcher
[−]
[src]
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)> { ... } }
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()
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
pattern
): API not fully fleshed out and ready to be stabilized
Getter for the underlaying string to be searched in
Will always return the same &str
fn next(&mut self) -> SearchStep
pattern
): API not fully fleshed out and ready to be stabilized
Performs the next search step starting from the front.
- Returns
Match(a, b)
ifhaystack[a..b]
matches the pattern. - Returns
Reject(a, b)
ifhaystack[a..b]
can not match the pattern, even partially. - Returns
Done
if every byte of the haystack has been visited
The stream of Match
and Reject
values up to a Done
will contain index ranges that are adjacent, non-overlapping,
covering the whole haystack, and laying on utf8 boundaries.
A Match
result needs to contain the whole matched pattern,
however 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)]
Provided Methods
fn next_match(&mut self) -> Option<(usize, usize)>
pattern
): API not fully fleshed out and ready to be stabilized
Find the next Match
result. See next()
fn next_reject(&mut self) -> Option<(usize, usize)>
pattern
): API not fully fleshed out and ready to be stabilized
Find the next Reject
result. See next()
Implementors
impl<'a, C> Searcher<'a> for CharEqSearcher<'a, C> where C: CharEq
impl<'a> Searcher<'a> for CharSearcher<'a>
impl<'a, 'b> Searcher<'a> for CharSliceSearcher<'a, 'b>
impl<'a, F> Searcher<'a> for CharPredicateSearcher<'a, F> where F: FnMut(char) -> bool
impl<'a, 'b> Searcher<'a> for StrSearcher<'a, 'b>