🔬This is a nightly-only experimental API. (
pattern
#27721)Expand description
The string Pattern API.
The Pattern API provides a generic mechanism for using different pattern types when searching through a string.
For more details, see the traits Pattern
, Searcher
,
ReverseSearcher
, and DoubleEndedSearcher
.
Although this API is unstable, it is exposed via stable APIs on the
str
type.
§Examples
Pattern
is implemented in the stable API for
&str
, char
, slices of char
, and functions and closures
implementing FnMut(char) -> bool
.
let s = "Can you find a needle in a haystack?";
// &str pattern
assert_eq!(s.find("you"), Some(4));
// char pattern
assert_eq!(s.find('n'), Some(2));
// array of chars pattern
assert_eq!(s.find(&['a', 'e', 'i', 'o', 'u']), Some(1));
// slice of chars pattern
assert_eq!(s.find(&['a', 'e', 'i', 'o', 'u'][..]), Some(1));
// closure pattern
assert_eq!(s.find(|c: char| c.is_ascii_punctuation()), Some(35));
RunStructs
- CharArrayRefSearcherExperimentalAssociated type for
<&[char; N] as Pattern<'a>>::Searcher
. - CharArraySearcherExperimentalAssociated type for
<[char; N] as Pattern<'a>>::Searcher
. - CharPredicateSearcherExperimentalAssociated type for
<F as Pattern<'a>>::Searcher
. - CharSearcherExperimentalAssociated type for
<char as Pattern<'a>>::Searcher
. - CharSliceSearcherExperimentalAssociated type for
<&[char] as Pattern<'a>>::Searcher
. - StrSearcherExperimentalAssociated type for
<&str as Pattern<'a>>::Searcher
.
Enums
- SearchStepExperimentalResult of calling
Searcher::next()
orReverseSearcher::next_back()
.
Traits
- DoubleEndedSearcherExperimentalA marker trait to express that a
ReverseSearcher
can be used for aDoubleEndedIterator
implementation. - PatternExperimentalA string pattern.
- ReverseSearcherExperimentalA reverse searcher for a string pattern.
- SearcherExperimentalA searcher for a string pattern.