| use std::borrow::Cow; |
| use std::collections::HashMap; |
| use std::fmt; |
| use std::ops::{Index, Range}; |
| use std::str::FromStr; |
| use std::sync::Arc; |
| |
| use find_byte::find_byte; |
| use syntax; |
| |
| use error::Error; |
| use exec::{Exec, ExecNoSyncStr}; |
| use expand::expand_str; |
| use re_builder::unicode::RegexBuilder; |
| use re_trait::{self, RegularExpression, SubCapturesPosIter}; |
| |
| /// Escapes all regular expression meta characters in `text`. |
| /// |
| /// The string returned may be safely used as a literal in a regular |
| /// expression. |
| pub fn escape(text: &str) -> String { |
| syntax::escape(text) |
| } |
| |
| /// Match represents a single match of a regex in a haystack. |
| /// |
| /// The lifetime parameter `'t` refers to the lifetime of the matched text. |
| #[derive(Copy, Clone, Debug, Eq, PartialEq)] |
| pub struct Match<'t> { |
| text: &'t str, |
| start: usize, |
| end: usize, |
| } |
| |
| impl<'t> Match<'t> { |
| /// Returns the starting byte offset of the match in the haystack. |
| #[inline] |
| pub fn start(&self) -> usize { |
| self.start |
| } |
| |
| /// Returns the ending byte offset of the match in the haystack. |
| #[inline] |
| pub fn end(&self) -> usize { |
| self.end |
| } |
| |
| /// Returns the range over the starting and ending byte offsets of the |
| /// match in the haystack. |
| #[inline] |
| pub fn range(&self) -> Range<usize> { |
| self.start..self.end |
| } |
| |
| /// Returns the matched text. |
| #[inline] |
| pub fn as_str(&self) -> &'t str { |
| &self.text[self.range()] |
| } |
| |
| /// Creates a new match from the given haystack and byte offsets. |
| #[inline] |
| fn new(haystack: &'t str, start: usize, end: usize) -> Match<'t> { |
| Match { text: haystack, start: start, end: end } |
| } |
| } |
| |
| impl<'t> From<Match<'t>> for &'t str { |
| fn from(m: Match<'t>) -> &'t str { |
| m.as_str() |
| } |
| } |
| |
| impl<'t> From<Match<'t>> for Range<usize> { |
| fn from(m: Match<'t>) -> Range<usize> { |
| m.range() |
| } |
| } |
| |
| /// A compiled regular expression for matching Unicode strings. |
| /// |
| /// It is represented as either a sequence of bytecode instructions (dynamic) |
| /// or as a specialized Rust function (native). It can be used to search, split |
| /// or replace text. All searching is done with an implicit `.*?` at the |
| /// beginning and end of an expression. To force an expression to match the |
| /// whole string (or a prefix or a suffix), you must use an anchor like `^` or |
| /// `$` (or `\A` and `\z`). |
| /// |
| /// While this crate will handle Unicode strings (whether in the regular |
| /// expression or in the search text), all positions returned are **byte |
| /// indices**. Every byte index is guaranteed to be at a Unicode code point |
| /// boundary. |
| /// |
| /// The lifetimes `'r` and `'t` in this crate correspond to the lifetime of a |
| /// compiled regular expression and text to search, respectively. |
| /// |
| /// The only methods that allocate new strings are the string replacement |
| /// methods. All other methods (searching and splitting) return borrowed |
| /// pointers into the string given. |
| /// |
| /// # Examples |
| /// |
| /// Find the location of a US phone number: |
| /// |
| /// ```rust |
| /// # use regex::Regex; |
| /// let re = Regex::new("[0-9]{3}-[0-9]{3}-[0-9]{4}").unwrap(); |
| /// let mat = re.find("phone: 111-222-3333").unwrap(); |
| /// assert_eq!((mat.start(), mat.end()), (7, 19)); |
| /// ``` |
| /// |
| /// # Using the `std::str::pattern` methods with `Regex` |
| /// |
| /// > **Note**: This section requires that this crate is compiled with the |
| /// > `pattern` Cargo feature enabled, which **requires nightly Rust**. |
| /// |
| /// Since `Regex` implements `Pattern`, you can use regexes with methods |
| /// defined on `&str`. For example, `is_match`, `find`, `find_iter` |
| /// and `split` can be replaced with `str::contains`, `str::find`, |
| /// `str::match_indices` and `str::split`. |
| /// |
| /// Here are some examples: |
| /// |
| /// ```rust,ignore |
| /// # use regex::Regex; |
| /// let re = Regex::new(r"\d+").unwrap(); |
| /// let haystack = "a111b222c"; |
| /// |
| /// assert!(haystack.contains(&re)); |
| /// assert_eq!(haystack.find(&re), Some(1)); |
| /// assert_eq!(haystack.match_indices(&re).collect::<Vec<_>>(), |
| /// vec![(1, 4), (5, 8)]); |
| /// assert_eq!(haystack.split(&re).collect::<Vec<_>>(), vec!["a", "b", "c"]); |
| /// ``` |
| #[derive(Clone)] |
| pub struct Regex(Exec); |
| |
| impl fmt::Display for Regex { |
| /// Shows the original regular expression. |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| write!(f, "{}", self.as_str()) |
| } |
| } |
| |
| impl fmt::Debug for Regex { |
| /// Shows the original regular expression. |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| fmt::Display::fmt(self, f) |
| } |
| } |
| |
| #[doc(hidden)] |
| impl From<Exec> for Regex { |
| fn from(exec: Exec) -> Regex { |
| Regex(exec) |
| } |
| } |
| |
| impl FromStr for Regex { |
| type Err = Error; |
| |
| /// Attempts to parse a string into a regular expression |
| fn from_str(s: &str) -> Result<Regex, Error> { |
| Regex::new(s) |
| } |
| } |
| |
| /// Core regular expression methods. |
| impl 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 new(re: &str) -> Result<Regex, Error> { |
| RegexBuilder::new(re).build() |
| } |
| |
| /// 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. |
| /// |
| /// # Example |
| /// |
| /// Test if some text contains at least one word with exactly 13 |
| /// Unicode word characters: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// let text = "I categorically deny having triskaidekaphobia."; |
| /// assert!(Regex::new(r"\b\w{13}\b").unwrap().is_match(text)); |
| /// # } |
| /// ``` |
| pub fn is_match(&self, text: &str) -> bool { |
| self.is_match_at(text, 0) |
| } |
| |
| /// 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`. |
| /// |
| /// # Example |
| /// |
| /// Find the start and end location of the first word with exactly 13 |
| /// Unicode word characters: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// 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<'t>(&self, text: &'t str) -> Option<Match<'t>> { |
| self.find_at(text, 0) |
| } |
| |
| /// Returns an iterator for each successive non-overlapping match in |
| /// `text`, returning the start and end byte indices with respect to |
| /// `text`. |
| /// |
| /// # Example |
| /// |
| /// Find the start and end location of every word with exactly 13 Unicode |
| /// word characters: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// 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 find_iter<'r, 't>(&'r self, text: &'t str) -> Matches<'r, 't> { |
| Matches(self.0.searcher_str().find_iter(text)) |
| } |
| |
| /// Returns the capture groups corresponding to the leftmost-first |
| /// match in `text`. Capture group `0` always corresponds to the entire |
| /// match. If no match is found, then `None` is returned. |
| /// |
| /// You should only use `captures` if you need access to the location of |
| /// capturing group matches. Otherwise, `find` is faster for discovering |
| /// the location of the overall match. |
| /// |
| /// # Examples |
| /// |
| /// Say you have some text with movie names and their release years, |
| /// like "'Citizen Kane' (1941)". It'd be nice if we could search for text |
| /// looking like that, while also extracting the movie name and its release |
| /// year separately. |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// let re = Regex::new(r"'([^']+)'\s+\((\d{4})\)").unwrap(); |
| /// let text = "Not my favorite movie: 'Citizen Kane' (1941)."; |
| /// let caps = re.captures(text).unwrap(); |
| /// assert_eq!(caps.get(1).unwrap().as_str(), "Citizen Kane"); |
| /// assert_eq!(caps.get(2).unwrap().as_str(), "1941"); |
| /// assert_eq!(caps.get(0).unwrap().as_str(), "'Citizen Kane' (1941)"); |
| /// // You can also access the groups by index using the Index notation. |
| /// // Note that this will panic on an invalid index. |
| /// assert_eq!(&caps[1], "Citizen Kane"); |
| /// assert_eq!(&caps[2], "1941"); |
| /// assert_eq!(&caps[0], "'Citizen Kane' (1941)"); |
| /// # } |
| /// ``` |
| /// |
| /// Note that the full match is at capture group `0`. Each subsequent |
| /// capture group is indexed by the order of its opening `(`. |
| /// |
| /// We can make this example a bit clearer by using *named* capture groups: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// let re = Regex::new(r"'(?P<title>[^']+)'\s+\((?P<year>\d{4})\)") |
| /// .unwrap(); |
| /// let text = "Not my favorite movie: 'Citizen Kane' (1941)."; |
| /// let caps = re.captures(text).unwrap(); |
| /// assert_eq!(caps.name("title").unwrap().as_str(), "Citizen Kane"); |
| /// assert_eq!(caps.name("year").unwrap().as_str(), "1941"); |
| /// assert_eq!(caps.get(0).unwrap().as_str(), "'Citizen Kane' (1941)"); |
| /// // You can also access the groups by name using the Index notation. |
| /// // Note that this will panic on an invalid group name. |
| /// assert_eq!(&caps["title"], "Citizen Kane"); |
| /// assert_eq!(&caps["year"], "1941"); |
| /// assert_eq!(&caps[0], "'Citizen Kane' (1941)"); |
| /// |
| /// # } |
| /// ``` |
| /// |
| /// Here we name the capture groups, which we can access with the `name` |
| /// method or the `Index` notation with a `&str`. Note that the named |
| /// capture groups are still accessible with `get` or the `Index` notation |
| /// with a `usize`. |
| /// |
| /// The `0`th capture group is always unnamed, so it must always be |
| /// accessed with `get(0)` or `[0]`. |
| pub fn captures<'t>(&self, text: &'t str) -> Option<Captures<'t>> { |
| let mut locs = self.capture_locations(); |
| self.captures_read_at(&mut locs, text, 0).map(move |_| Captures { |
| text: text, |
| locs: locs.0, |
| named_groups: self.0.capture_name_idx().clone(), |
| }) |
| } |
| |
| /// Returns an iterator over all the non-overlapping capture groups matched |
| /// in `text`. This is operationally the same as `find_iter`, except it |
| /// yields information about capturing group matches. |
| /// |
| /// # Example |
| /// |
| /// We can use this to find all movie titles and their release years in |
| /// some text, where the movie is formatted like "'Title' (xxxx)": |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// let re = Regex::new(r"'(?P<title>[^']+)'\s+\((?P<year>\d{4})\)") |
| /// .unwrap(); |
| /// let text = "'Citizen Kane' (1941), 'The Wizard of Oz' (1939), 'M' (1931)."; |
| /// for caps in re.captures_iter(text) { |
| /// println!("Movie: {:?}, Released: {:?}", |
| /// &caps["title"], &caps["year"]); |
| /// } |
| /// // Output: |
| /// // Movie: Citizen Kane, Released: 1941 |
| /// // Movie: The Wizard of Oz, Released: 1939 |
| /// // Movie: M, Released: 1931 |
| /// # } |
| /// ``` |
| pub fn captures_iter<'r, 't>( |
| &'r self, |
| text: &'t str, |
| ) -> CaptureMatches<'r, 't> { |
| CaptureMatches(self.0.searcher_str().captures_iter(text)) |
| } |
| |
| /// 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. |
| /// |
| /// # Example |
| /// |
| /// To split a string delimited by arbitrary amounts of spaces or tabs: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// 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 split<'r, 't>(&'r self, text: &'t str) -> Split<'r, 't> { |
| Split { finder: self.find_iter(text), last: 0 } |
| } |
| |
| /// 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. |
| /// |
| /// # Example |
| /// |
| /// Get the first two words in some text: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// 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?")); |
| /// # } |
| /// ``` |
| pub fn splitn<'r, 't>( |
| &'r self, |
| text: &'t str, |
| limit: usize, |
| ) -> SplitN<'r, 't> { |
| SplitN { splits: self.split(text), n: limit } |
| } |
| |
| /// Replaces the leftmost-first match with the replacement provided. |
| /// The replacement can be a regular string (where `$N` and `$name` are |
| /// expanded to match capture groups) or a function that takes the matches' |
| /// `Captures` and returns the replaced string. |
| /// |
| /// If no match is found, then a copy of the string is returned unchanged. |
| /// |
| /// # Replacement string syntax |
| /// |
| /// All instances of `$name` in the replacement text is replaced with the |
| /// corresponding capture group `name`. |
| /// |
| /// `name` may be an integer corresponding to the index of the |
| /// capture group (counted by order of opening parenthesis where `0` is the |
| /// entire match) or it can be a name (consisting of letters, digits or |
| /// underscores) corresponding to a named capture group. |
| /// |
| /// If `name` isn't a valid capture group (whether the name doesn't exist |
| /// or isn't a valid index), then it is replaced with the empty string. |
| /// |
| /// The longest possible name is used. e.g., `$1a` looks up the capture |
| /// group named `1a` and not the capture group at index `1`. To exert more |
| /// precise control over the name, use braces, e.g., `${1}a`. |
| /// |
| /// To write a literal `$` use `$$`. |
| /// |
| /// # Examples |
| /// |
| /// Note that this function is polymorphic with respect to the replacement. |
| /// In typical usage, this can just be a normal string: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// let re = Regex::new("[^01]+").unwrap(); |
| /// assert_eq!(re.replace("1078910", ""), "1010"); |
| /// # } |
| /// ``` |
| /// |
| /// But anything satisfying the `Replacer` trait will work. For example, |
| /// a closure of type `|&Captures| -> String` provides direct access to the |
| /// captures corresponding to a match. This allows one to access |
| /// capturing group matches easily: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # use regex::Captures; fn main() { |
| /// let re = Regex::new(r"([^,\s]+),\s+(\S+)").unwrap(); |
| /// let result = re.replace("Springsteen, Bruce", |caps: &Captures| { |
| /// format!("{} {}", &caps[2], &caps[1]) |
| /// }); |
| /// assert_eq!(result, "Bruce Springsteen"); |
| /// # } |
| /// ``` |
| /// |
| /// But this is a bit cumbersome to use all the time. Instead, a simple |
| /// syntax is supported that expands `$name` into the corresponding capture |
| /// group. Here's the last example, but using this expansion technique |
| /// with named capture groups: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// let re = Regex::new(r"(?P<last>[^,\s]+),\s+(?P<first>\S+)").unwrap(); |
| /// let result = re.replace("Springsteen, Bruce", "$first $last"); |
| /// assert_eq!(result, "Bruce Springsteen"); |
| /// # } |
| /// ``` |
| /// |
| /// Note that using `$2` instead of `$first` or `$1` instead of `$last` |
| /// would produce the same result. To write a literal `$` use `$$`. |
| /// |
| /// Sometimes the replacement string requires use of curly braces to |
| /// delineate a capture group replacement and surrounding literal text. |
| /// For example, if we wanted to join two words together with an |
| /// underscore: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// let re = Regex::new(r"(?P<first>\w+)\s+(?P<second>\w+)").unwrap(); |
| /// let result = re.replace("deep fried", "${first}_$second"); |
| /// assert_eq!(result, "deep_fried"); |
| /// # } |
| /// ``` |
| /// |
| /// Without the curly braces, the capture group name `first_` would be |
| /// used, and since it doesn't exist, it would be replaced with the empty |
| /// string. |
| /// |
| /// Finally, sometimes you just want to replace a literal string with no |
| /// regard for capturing group expansion. This can be done by wrapping a |
| /// byte string with `NoExpand`: |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// use regex::NoExpand; |
| /// |
| /// let re = Regex::new(r"(?P<last>[^,\s]+),\s+(\S+)").unwrap(); |
| /// let result = re.replace("Springsteen, Bruce", NoExpand("$2 $last")); |
| /// assert_eq!(result, "$2 $last"); |
| /// # } |
| /// ``` |
| pub fn replace<'t, R: Replacer>( |
| &self, |
| text: &'t str, |
| rep: R, |
| ) -> Cow<'t, str> { |
| self.replacen(text, 1, rep) |
| } |
| |
| /// Replaces all non-overlapping matches in `text` with the replacement |
| /// provided. This is the same as calling `replacen` with `limit` set to |
| /// `0`. |
| /// |
| /// See the documentation for `replace` for details on how to access |
| /// capturing group matches in the replacement string. |
| pub fn replace_all<'t, R: Replacer>( |
| &self, |
| text: &'t str, |
| rep: R, |
| ) -> Cow<'t, str> { |
| self.replacen(text, 0, rep) |
| } |
| |
| /// Replaces at most `limit` non-overlapping matches in `text` with the |
| /// replacement provided. If `limit` is 0, then all non-overlapping matches |
| /// are replaced. |
| /// |
| /// See the documentation for `replace` for details on how to access |
| /// capturing group matches in the replacement string. |
| pub fn replacen<'t, R: Replacer>( |
| &self, |
| text: &'t str, |
| limit: usize, |
| mut rep: R, |
| ) -> Cow<'t, str> { |
| // If we know that the replacement doesn't have any capture expansions, |
| // then we can fast path. The fast path can make a tremendous |
| // difference: |
| // |
| // 1) We use `find_iter` instead of `captures_iter`. Not asking for |
| // captures generally makes the regex engines faster. |
| // 2) We don't need to look up all of the capture groups and do |
| // replacements inside the replacement string. We just push it |
| // at each match and be done with it. |
| if let Some(rep) = rep.no_expansion() { |
| let mut it = self.find_iter(text).enumerate().peekable(); |
| if it.peek().is_none() { |
| return Cow::Borrowed(text); |
| } |
| let mut new = String::with_capacity(text.len()); |
| let mut last_match = 0; |
| for (i, m) in it { |
| if limit > 0 && i >= limit { |
| break; |
| } |
| new.push_str(&text[last_match..m.start()]); |
| new.push_str(&rep); |
| last_match = m.end(); |
| } |
| new.push_str(&text[last_match..]); |
| return Cow::Owned(new); |
| } |
| |
| // The slower path, which we use if the replacement needs access to |
| // capture groups. |
| let mut it = self.captures_iter(text).enumerate().peekable(); |
| if it.peek().is_none() { |
| return Cow::Borrowed(text); |
| } |
| let mut new = String::with_capacity(text.len()); |
| let mut last_match = 0; |
| for (i, cap) in it { |
| if limit > 0 && i >= limit { |
| break; |
| } |
| // unwrap on 0 is OK because captures only reports matches |
| let m = cap.get(0).unwrap(); |
| new.push_str(&text[last_match..m.start()]); |
| rep.replace_append(&cap, &mut new); |
| last_match = m.end(); |
| } |
| new.push_str(&text[last_match..]); |
| Cow::Owned(new) |
| } |
| } |
| |
| /// Advanced or "lower level" search methods. |
| impl Regex { |
| /// Returns the end location of a match in the text given. |
| /// |
| /// This method may have the same performance characteristics as |
| /// `is_match`, except it provides an end location for a match. In |
| /// particular, the location returned *may be shorter* than the proper end |
| /// of the leftmost-first match. |
| /// |
| /// # Example |
| /// |
| /// Typically, `a+` would match the entire first sequence of `a` in some |
| /// text, but `shortest_match` can give up as soon as it sees the first |
| /// `a`. |
| /// |
| /// ```rust |
| /// # extern crate regex; use regex::Regex; |
| /// # fn main() { |
| /// let text = "aaaaa"; |
| /// let pos = Regex::new(r"a+").unwrap().shortest_match(text); |
| /// assert_eq!(pos, Some(1)); |
| /// # } |
| /// ``` |
| pub fn shortest_match(&self, text: &str) -> Option<usize> { |
| self.shortest_match_at(text, 0) |
| } |
| |
| /// Returns the same as shortest_match, but starts the search at the given |
| /// offset. |
| /// |
| /// The significance of the starting point is that it takes the surrounding |
| /// context into consideration. For example, the `\A` anchor can only |
| /// match when `start == 0`. |
| pub fn shortest_match_at( |
| &self, |
| text: &str, |
| start: usize, |
| ) -> Option<usize> { |
| self.0.searcher_str().shortest_match_at(text, start) |
| } |
| |
| /// Returns the same as is_match, but starts the search at the given |
| /// offset. |
| /// |
| /// The significance of the starting point is that it takes the surrounding |
| /// context into consideration. For example, the `\A` anchor can only |
| /// match when `start == 0`. |
| pub fn is_match_at(&self, text: &str, start: usize) -> bool { |
| self.shortest_match_at(text, start).is_some() |
| } |
| |
| /// Returns the same as find, but starts the search at the given |
| /// offset. |
| /// |
| /// The significance of the starting point is that it takes the surrounding |
| /// context into consideration. For example, the `\A` anchor can only |
| /// match when `start == 0`. |
| pub fn find_at<'t>( |
| &self, |
| text: &'t str, |
| start: usize, |
| ) -> Option<Match<'t>> { |
| self.0 |
| .searcher_str() |
| .find_at(text, start) |
| .map(|(s, e)| Match::new(text, s, e)) |
| } |
| |
| /// This is like `captures`, but uses |
| /// [`CaptureLocations`](struct.CaptureLocations.html) |
| /// instead of |
| /// [`Captures`](struct.Captures.html) in order to amortize allocations. |
| /// |
| /// To create a `CaptureLocations` value, use the |
| /// `Regex::capture_locations` method. |
| /// |
| /// This returns the overall match if this was successful, which is always |
| /// equivalence to the `0`th capture group. |
| pub fn captures_read<'t>( |
| &self, |
| locs: &mut CaptureLocations, |
| text: &'t str, |
| ) -> Option<Match<'t>> { |
| self.captures_read_at(locs, text, 0) |
| } |
| |
| /// Returns the same as captures, but starts the search at the given |
| /// offset and populates the capture locations given. |
| /// |
| /// The significance of the starting point is that it takes the surrounding |
| /// context into consideration. For example, the `\A` anchor can only |
| /// match when `start == 0`. |
| pub fn captures_read_at<'t>( |
| &self, |
| locs: &mut CaptureLocations, |
| text: &'t str, |
| start: usize, |
| ) -> Option<Match<'t>> { |
| self.0 |
| .searcher_str() |
| .captures_read_at(&mut locs.0, text, start) |
| .map(|(s, e)| Match::new(text, s, e)) |
| } |
| |
| /// An undocumented alias for `captures_read_at`. |
| /// |
| /// The `regex-capi` crate previously used this routine, so to avoid |
| /// breaking that crate, we continue to provide the name as an undocumented |
| /// alias. |
| #[doc(hidden)] |
| pub fn read_captures_at<'t>( |
| &self, |
| locs: &mut CaptureLocations, |
| text: &'t str, |
| start: usize, |
| ) -> Option<Match<'t>> { |
| self.captures_read_at(locs, text, start) |
| } |
| } |
| |
| /// Auxiliary methods. |
| impl Regex { |
| /// Returns the original string of this regex. |
| pub fn as_str(&self) -> &str { |
| &self.0.regex_strings()[0] |
| } |
| |
| /// Returns an iterator over the capture names. |
| pub fn capture_names(&self) -> CaptureNames { |
| CaptureNames(self.0.capture_names().iter()) |
| } |
| |
| /// Returns the number of captures. |
| pub fn captures_len(&self) -> usize { |
| self.0.capture_names().len() |
| } |
| |
| /// Returns an empty set of capture locations that can be reused in |
| /// multiple calls to `captures_read` or `captures_read_at`. |
| pub fn capture_locations(&self) -> CaptureLocations { |
| CaptureLocations(self.0.searcher_str().locations()) |
| } |
| |
| /// An alias for `capture_locations` to preserve backward compatibility. |
| /// |
| /// The `regex-capi` crate uses this method, so to avoid breaking that |
| /// crate, we continue to export it as an undocumented API. |
| #[doc(hidden)] |
| pub fn locations(&self) -> CaptureLocations { |
| CaptureLocations(self.0.searcher_str().locations()) |
| } |
| } |
| |
| /// An iterator over the names of all possible captures. |
| /// |
| /// `None` indicates an unnamed capture; the first element (capture 0, the |
| /// whole matched region) is always unnamed. |
| /// |
| /// `'r` is the lifetime of the compiled regular expression. |
| pub struct CaptureNames<'r>(::std::slice::Iter<'r, Option<String>>); |
| |
| impl<'r> Iterator for CaptureNames<'r> { |
| type Item = Option<&'r str>; |
| |
| fn next(&mut self) -> Option<Option<&'r str>> { |
| self.0 |
| .next() |
| .as_ref() |
| .map(|slot| slot.as_ref().map(|name| name.as_ref())) |
| } |
| |
| fn size_hint(&self) -> (usize, Option<usize>) { |
| self.0.size_hint() |
| } |
| } |
| |
| /// Yields all substrings delimited by a regular expression match. |
| /// |
| /// `'r` is the lifetime of the compiled regular expression and `'t` is the |
| /// lifetime of the string being split. |
| pub struct Split<'r, 't> { |
| finder: Matches<'r, 't>, |
| last: usize, |
| } |
| |
| impl<'r, 't> Iterator for Split<'r, 't> { |
| type Item = &'t str; |
| |
| fn next(&mut self) -> Option<&'t str> { |
| let text = self.finder.0.text(); |
| match self.finder.next() { |
| None => { |
| if self.last > text.len() { |
| None |
| } else { |
| let s = &text[self.last..]; |
| self.last = text.len() + 1; // Next call will return None |
| Some(s) |
| } |
| } |
| Some(m) => { |
| let matched = &text[self.last..m.start()]; |
| self.last = m.end(); |
| Some(matched) |
| } |
| } |
| } |
| } |
| |
| /// Yields at most `N` substrings delimited by a regular expression match. |
| /// |
| /// The last substring will be whatever remains after splitting. |
| /// |
| /// `'r` is the lifetime of the compiled regular expression and `'t` is the |
| /// lifetime of the string being split. |
| pub struct SplitN<'r, 't> { |
| splits: Split<'r, 't>, |
| n: usize, |
| } |
| |
| impl<'r, 't> Iterator for SplitN<'r, 't> { |
| type Item = &'t str; |
| |
| fn next(&mut self) -> Option<&'t str> { |
| if self.n == 0 { |
| return None; |
| } |
| |
| self.n -= 1; |
| if self.n > 0 { |
| return self.splits.next(); |
| } |
| |
| let text = self.splits.finder.0.text(); |
| if self.splits.last > text.len() { |
| // We've already returned all substrings. |
| None |
| } else { |
| // self.n == 0, so future calls will return None immediately |
| Some(&text[self.splits.last..]) |
| } |
| } |
| } |
| |
| /// CaptureLocations is a low level representation of the raw offsets of each |
| /// submatch. |
| /// |
| /// You can think of this as a lower level |
| /// [`Captures`](struct.Captures.html), where this type does not support |
| /// named capturing groups directly and it does not borrow the text that these |
| /// offsets were matched on. |
| /// |
| /// Primarily, this type is useful when using the lower level `Regex` APIs |
| /// such as `read_captures`, which permits amortizing the allocation in which |
| /// capture match locations are stored. |
| /// |
| /// In order to build a value of this type, you'll need to call the |
| /// `capture_locations` method on the `Regex` being used to execute the search. |
| /// The value returned can then be reused in subsequent searches. |
| #[derive(Clone, Debug)] |
| pub struct CaptureLocations(re_trait::Locations); |
| |
| /// A type alias for `CaptureLocations` for backwards compatibility. |
| /// |
| /// Previously, we exported `CaptureLocations` as `Locations` in an |
| /// undocumented API. To prevent breaking that code (e.g., in `regex-capi`), |
| /// we continue re-exporting the same undocumented API. |
| #[doc(hidden)] |
| pub type Locations = CaptureLocations; |
| |
| impl CaptureLocations { |
| /// Returns the start and end positions of the Nth capture group. Returns |
| /// `None` if `i` is not a valid capture group or if the capture group did |
| /// not match anything. The positions returned are *always* byte indices |
| /// with respect to the original string matched. |
| #[inline] |
| pub fn get(&self, i: usize) -> Option<(usize, usize)> { |
| self.0.pos(i) |
| } |
| |
| /// Returns the total number of capturing groups. |
| /// |
| /// This is always at least `1` since every regex has at least `1` |
| /// capturing group that corresponds to the entire match. |
| #[inline] |
| pub fn len(&self) -> usize { |
| self.0.len() |
| } |
| |
| /// An alias for the `get` method for backwards compatibility. |
| /// |
| /// Previously, we exported `get` as `pos` in an undocumented API. To |
| /// prevent breaking that code (e.g., in `regex-capi`), we continue |
| /// re-exporting the same undocumented API. |
| #[doc(hidden)] |
| #[inline] |
| pub fn pos(&self, i: usize) -> Option<(usize, usize)> { |
| self.get(i) |
| } |
| } |
| |
| /// Captures represents a group of captured strings for a single match. |
| /// |
| /// The 0th capture always corresponds to the entire match. Each subsequent |
| /// index corresponds to the next capture group in the regex. If a capture |
| /// group is named, then the matched string is *also* available via the `name` |
| /// method. (Note that the 0th capture is always unnamed and so must be |
| /// accessed with the `get` method.) |
| /// |
| /// Positions returned from a capture group are always byte indices. |
| /// |
| /// `'t` is the lifetime of the matched text. |
| pub struct Captures<'t> { |
| text: &'t str, |
| locs: re_trait::Locations, |
| named_groups: Arc<HashMap<String, usize>>, |
| } |
| |
| impl<'t> Captures<'t> { |
| /// Returns the match associated with the capture group at index `i`. If |
| /// `i` does not correspond to a capture group, or if the capture group |
| /// did not participate in the match, then `None` is returned. |
| /// |
| /// # Examples |
| /// |
| /// Get the text of the match with a default of an empty string if this |
| /// group didn't participate in the match: |
| /// |
| /// ```rust |
| /// # use regex::Regex; |
| /// let re = Regex::new(r"[a-z]+(?:([0-9]+)|([A-Z]+))").unwrap(); |
| /// let caps = re.captures("abc123").unwrap(); |
| /// |
| /// let text1 = caps.get(1).map_or("", |m| m.as_str()); |
| /// let text2 = caps.get(2).map_or("", |m| m.as_str()); |
| /// assert_eq!(text1, "123"); |
| /// assert_eq!(text2, ""); |
| /// ``` |
| pub fn get(&self, i: usize) -> Option<Match<'t>> { |
| self.locs.pos(i).map(|(s, e)| Match::new(self.text, s, e)) |
| } |
| |
| /// Returns the match for the capture group named `name`. If `name` isn't a |
| /// valid capture group or didn't match anything, then `None` is returned. |
| pub fn name(&self, name: &str) -> Option<Match<'t>> { |
| self.named_groups.get(name).and_then(|&i| self.get(i)) |
| } |
| |
| /// An iterator that yields all capturing matches in the order in which |
| /// they appear in the regex. If a particular capture group didn't |
| /// participate in the match, then `None` is yielded for that capture. |
| /// |
| /// The first match always corresponds to the overall match of the regex. |
| pub fn iter<'c>(&'c self) -> SubCaptureMatches<'c, 't> { |
| SubCaptureMatches { caps: self, it: self.locs.iter() } |
| } |
| |
| /// Expands all instances of `$name` in `replacement` to the corresponding |
| /// capture group `name`, and writes them to the `dst` buffer given. |
| /// |
| /// `name` may be an integer corresponding to the index of the |
| /// capture group (counted by order of opening parenthesis where `0` is the |
| /// entire match) or it can be a name (consisting of letters, digits or |
| /// underscores) corresponding to a named capture group. |
| /// |
| /// If `name` isn't a valid capture group (whether the name doesn't exist |
| /// or isn't a valid index), then it is replaced with the empty string. |
| /// |
| /// The longest possible name is used. e.g., `$1a` looks up the capture |
| /// group named `1a` and not the capture group at index `1`. To exert more |
| /// precise control over the name, use braces, e.g., `${1}a`. |
| /// |
| /// To write a literal `$` use `$$`. |
| pub fn expand(&self, replacement: &str, dst: &mut String) { |
| expand_str(self, replacement, dst) |
| } |
| |
| /// Returns the number of captured groups. |
| /// |
| /// This is always at least `1`, since every regex has at least one capture |
| /// group that corresponds to the full match. |
| #[inline] |
| pub fn len(&self) -> usize { |
| self.locs.len() |
| } |
| } |
| |
| impl<'t> fmt::Debug for Captures<'t> { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| f.debug_tuple("Captures").field(&CapturesDebug(self)).finish() |
| } |
| } |
| |
| struct CapturesDebug<'c, 't: 'c>(&'c Captures<'t>); |
| |
| impl<'c, 't> fmt::Debug for CapturesDebug<'c, 't> { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| // We'd like to show something nice here, even if it means an |
| // allocation to build a reverse index. |
| let slot_to_name: HashMap<&usize, &String> = |
| self.0.named_groups.iter().map(|(a, b)| (b, a)).collect(); |
| let mut map = f.debug_map(); |
| for (slot, m) in self.0.locs.iter().enumerate() { |
| let m = m.map(|(s, e)| &self.0.text[s..e]); |
| if let Some(name) = slot_to_name.get(&slot) { |
| map.entry(&name, &m); |
| } else { |
| map.entry(&slot, &m); |
| } |
| } |
| map.finish() |
| } |
| } |
| |
| /// Get a group by index. |
| /// |
| /// `'t` is the lifetime of the matched text. |
| /// |
| /// The text can't outlive the `Captures` object if this method is |
| /// used, because of how `Index` is defined (normally `a[i]` is part |
| /// of `a` and can't outlive it); to do that, use `get()` instead. |
| /// |
| /// # Panics |
| /// |
| /// If there is no group at the given index. |
| impl<'t> Index<usize> for Captures<'t> { |
| type Output = str; |
| |
| fn index(&self, i: usize) -> &str { |
| self.get(i) |
| .map(|m| m.as_str()) |
| .unwrap_or_else(|| panic!("no group at index '{}'", i)) |
| } |
| } |
| |
| /// Get a group by name. |
| /// |
| /// `'t` is the lifetime of the matched text and `'i` is the lifetime |
| /// of the group name (the index). |
| /// |
| /// The text can't outlive the `Captures` object if this method is |
| /// used, because of how `Index` is defined (normally `a[i]` is part |
| /// of `a` and can't outlive it); to do that, use `name` instead. |
| /// |
| /// # Panics |
| /// |
| /// If there is no group named by the given value. |
| impl<'t, 'i> Index<&'i str> for Captures<'t> { |
| type Output = str; |
| |
| fn index<'a>(&'a self, name: &'i str) -> &'a str { |
| self.name(name) |
| .map(|m| m.as_str()) |
| .unwrap_or_else(|| panic!("no group named '{}'", name)) |
| } |
| } |
| |
| /// An iterator that yields all capturing matches in the order in which they |
| /// appear in the regex. |
| /// |
| /// If a particular capture group didn't participate in the match, then `None` |
| /// is yielded for that capture. The first match always corresponds to the |
| /// overall match of the regex. |
| /// |
| /// The lifetime `'c` corresponds to the lifetime of the `Captures` value, and |
| /// the lifetime `'t` corresponds to the originally matched text. |
| pub struct SubCaptureMatches<'c, 't: 'c> { |
| caps: &'c Captures<'t>, |
| it: SubCapturesPosIter<'c>, |
| } |
| |
| impl<'c, 't> Iterator for SubCaptureMatches<'c, 't> { |
| type Item = Option<Match<'t>>; |
| |
| fn next(&mut self) -> Option<Option<Match<'t>>> { |
| self.it |
| .next() |
| .map(|cap| cap.map(|(s, e)| Match::new(self.caps.text, s, e))) |
| } |
| } |
| |
| /// An iterator that yields all non-overlapping capture groups matching a |
| /// particular regular expression. |
| /// |
| /// The iterator stops when no more matches can be found. |
| /// |
| /// `'r` is the lifetime of the compiled regular expression and `'t` is the |
| /// lifetime of the matched string. |
| pub struct CaptureMatches<'r, 't>( |
| re_trait::CaptureMatches<'t, ExecNoSyncStr<'r>>, |
| ); |
| |
| impl<'r, 't> Iterator for CaptureMatches<'r, 't> { |
| type Item = Captures<'t>; |
| |
| fn next(&mut self) -> Option<Captures<'t>> { |
| self.0.next().map(|locs| Captures { |
| text: self.0.text(), |
| locs: locs, |
| named_groups: self.0.regex().capture_name_idx().clone(), |
| }) |
| } |
| } |
| |
| /// An iterator over all non-overlapping matches for a particular string. |
| /// |
| /// The iterator yields a `Match` value. The iterator stops when no more |
| /// matches can be found. |
| /// |
| /// `'r` is the lifetime of the compiled regular expression and `'t` is the |
| /// lifetime of the matched string. |
| pub struct Matches<'r, 't>(re_trait::Matches<'t, ExecNoSyncStr<'r>>); |
| |
| impl<'r, 't> Iterator for Matches<'r, 't> { |
| type Item = Match<'t>; |
| |
| fn next(&mut self) -> Option<Match<'t>> { |
| let text = self.0.text(); |
| self.0.next().map(|(s, e)| Match::new(text, s, e)) |
| } |
| } |
| |
| /// Replacer describes types that can be used to replace matches in a string. |
| /// |
| /// In general, users of this crate shouldn't need to implement this trait, |
| /// since implementations are already provided for `&str` and |
| /// `FnMut(&Captures) -> String` (or any `FnMut(&Captures) -> T` |
| /// where `T: AsRef<str>`), which covers most use cases. |
| pub trait Replacer { |
| /// Appends text to `dst` to replace the current match. |
| /// |
| /// The current match is represented by `caps`, which is guaranteed to |
| /// have a match at capture group `0`. |
| /// |
| /// For example, a no-op replacement would be |
| /// `dst.extend(caps.get(0).unwrap().as_str())`. |
| fn replace_append(&mut self, caps: &Captures, dst: &mut String); |
| |
| /// Return a fixed unchanging replacement string. |
| /// |
| /// When doing replacements, if access to `Captures` is not needed (e.g., |
| /// the replacement byte string does not need `$` expansion), then it can |
| /// be beneficial to avoid finding sub-captures. |
| /// |
| /// In general, this is called once for every call to `replacen`. |
| fn no_expansion<'r>(&'r mut self) -> Option<Cow<'r, str>> { |
| None |
| } |
| |
| /// Return a `Replacer` that borrows and wraps this `Replacer`. |
| /// |
| /// This is useful when you want to take a generic `Replacer` (which might |
| /// not be cloneable) and use it without consuming it, so it can be used |
| /// more than once. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| /// use regex::{Regex, Replacer}; |
| /// |
| /// fn replace_all_twice<R: Replacer>( |
| /// re: Regex, |
| /// src: &str, |
| /// mut rep: R, |
| /// ) -> String { |
| /// let dst = re.replace_all(src, rep.by_ref()); |
| /// let dst = re.replace_all(&dst, rep.by_ref()); |
| /// dst.into_owned() |
| /// } |
| /// ``` |
| fn by_ref<'r>(&'r mut self) -> ReplacerRef<'r, Self> { |
| ReplacerRef(self) |
| } |
| } |
| |
| /// By-reference adaptor for a `Replacer` |
| /// |
| /// Returned by [`Replacer::by_ref`](trait.Replacer.html#method.by_ref). |
| #[derive(Debug)] |
| pub struct ReplacerRef<'a, R: ?Sized + 'a>(&'a mut R); |
| |
| impl<'a, R: Replacer + ?Sized + 'a> Replacer for ReplacerRef<'a, R> { |
| fn replace_append(&mut self, caps: &Captures, dst: &mut String) { |
| self.0.replace_append(caps, dst) |
| } |
| fn no_expansion(&mut self) -> Option<Cow<str>> { |
| self.0.no_expansion() |
| } |
| } |
| |
| impl<'a> Replacer for &'a str { |
| fn replace_append(&mut self, caps: &Captures, dst: &mut String) { |
| caps.expand(*self, dst); |
| } |
| |
| fn no_expansion(&mut self) -> Option<Cow<str>> { |
| match find_byte(b'$', self.as_bytes()) { |
| Some(_) => None, |
| None => Some(Cow::Borrowed(*self)), |
| } |
| } |
| } |
| |
| impl<F, T> Replacer for F |
| where |
| F: FnMut(&Captures) -> T, |
| T: AsRef<str>, |
| { |
| fn replace_append(&mut self, caps: &Captures, dst: &mut String) { |
| dst.push_str((*self)(caps).as_ref()); |
| } |
| } |
| |
| /// `NoExpand` indicates literal string replacement. |
| /// |
| /// It can be used with `replace` and `replace_all` to do a literal string |
| /// replacement without expanding `$name` to their corresponding capture |
| /// groups. This can be both convenient (to avoid escaping `$`, for example) |
| /// and performant (since capture groups don't need to be found). |
| /// |
| /// `'t` is the lifetime of the literal text. |
| pub struct NoExpand<'t>(pub &'t str); |
| |
| impl<'t> Replacer for NoExpand<'t> { |
| fn replace_append(&mut self, _: &Captures, dst: &mut String) { |
| dst.push_str(self.0); |
| } |
| |
| fn no_expansion(&mut self) -> Option<Cow<str>> { |
| Some(Cow::Borrowed(self.0)) |
| } |
| } |
