Struct hyperscan::regex::Regex

pub struct Regex(_);

A compiled regular expression for matching Unicode strings.

Implementations

impl Regex

Core regular expression methods.

pub fn new<S: Into<String>>(re: S) -> Result<Regex>

Compiles a regular expression. Once compiled, it can be used repeatedly to search, split or replace text in a string.

If an invalid expression is given, then an error is returned.

pub fn is_match(&self, text: &str) -> bool

Returns true if and only if the regex matches the string given.

It is recommended to use this method if all you need to do is test a match, since the underlying matching engine may be able to do less work.

Examples

Test if some text contains at least one word with exactly 13 Unicode word characters:

let text = "I categorically deny having triskaidekaphobia.";
assert!(Regex::new(r"\b\w{13}\b").unwrap().is_match(text));

pub fn find<'t>(&self, text: &'t str) -> Option<Match<'t>>

Returns the start and end byte range of the leftmost-first match in text. If no match exists, then None is returned.

Note that this should only be used if you want to discover the position of the match. Testing the existence of a match is faster if you use is_match.

Examples

Find the start and end location of the first word with exactly 13 Unicode word characters:

let text = "I categorically deny having triskaidekaphobia.";
let mat = Regex::new(r"\b\w{13}\b").unwrap().find(text).unwrap();
assert_eq!(mat.start(), 2);
assert_eq!(mat.end(), 15);

pub fn find_iter<'t>(&self, text: &'t str) -> Matches<'t>

Returns an iterator for each successive non-overlapping match in text, returning the start and end byte indices with respect to text.

Examples

Find the start and end location of every word with exactly 13 Unicode word characters:

let text = "Retroactively relinquishing remunerations is reprehensible.";
for mat in Regex::new(r"\b\w{13}\b").unwrap().find_iter(text) {
    println!("{:?}", mat);
}

pub fn split<'t>(&self, text: &'t str) -> Split<'t>

Returns an iterator of substrings of text delimited by a match of the regular expression. Namely, each element of the iterator corresponds to text that isn’t matched by the regular expression.

This method will not copy the text given.

Examples

To split a string delimited by arbitrary amounts of spaces or tabs:

let re = Regex::new(r"[ \t]+").unwrap();
let fields: Vec<&str> = re.split("a b \t  c\td    e").collect();
assert_eq!(fields, vec!["a", "b", "c", "d", "e"]);

pub fn splitn<'t>(&self, text: &'t str, limit: usize) -> SplitN<'t>

Returns an iterator of at most limit substrings of text delimited by a match of the regular expression. (A limit of 0 will return no substrings.) Namely, each element of the iterator corresponds to text that isn’t matched by the regular expression. The remainder of the string that is not split will be the last element in the iterator.

This method will not copy the text given.

Examples

Get the first two words in some text:

let re = Regex::new(r"\W+").unwrap();
let fields: Vec<&str> = re.splitn("Hey! How are you?", 3).collect();
assert_eq!(fields, vec!("Hey", "How", "are you?"));

Trait Implementations

impl Clone for Regex

fn clone(&self) -> Regex

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl FromStr for Regex

fn from_str(s: &str) -> Result<Regex>

Attempts to parse a string into a regular expression

type Err = Error

The associated error which can be returned from parsing.