1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 use std::collections::HashMap;
13 use std::str::{MaybeOwned, Owned, Slice};
18 use vm::{CaptureLocs, MatchKind, Exists, Location, Submatches};
20 /// Escapes all regular expression meta characters in `text`.
22 /// The string returned may be safely used as a literal in a regular
24 pub fn quote(text: &str) -> String {
25 let mut quoted = String::with_capacity(text.len());
26 for c in text.chars() {
27 if parse::is_punct(c) {
35 /// Tests if the given regular expression matches somewhere in the text given.
37 /// If there was a problem compiling the regular expression, an error is
40 /// To find submatches, split or replace text, you'll need to compile an
43 /// Note that you should prefer the `regex!` macro when possible. For example,
44 /// `regex!("...").is_match("...")`.
45 pub fn is_match(regex: &str, text: &str) -> Result<bool, parse::Error> {
46 Regex::new(regex).map(|r| r.is_match(text))
49 /// A compiled regular expression
51 /// It is represented as either a sequence of bytecode instructions (dynamic)
52 /// or as a specialized Rust function (native). It can be used to search, split
53 /// or replace text. All searching is done with an implicit `.*?` at the
54 /// beginning and end of an expression. To force an expression to match the
55 /// whole string (or a prefix or a suffix), you must use an anchor like `^` or
56 /// `$` (or `\A` and `\z`).
58 /// While this crate will handle Unicode strings (whether in the regular
59 /// expression or in the search text), all positions returned are **byte
60 /// indices**. Every byte index is guaranteed to be at a Unicode code point
63 /// The lifetimes `'r` and `'t` in this crate correspond to the lifetime of a
64 /// compiled regular expression and text to search, respectively.
66 /// The only methods that allocate new strings are the string replacement
67 /// methods. All other methods (searching and splitting) return borrowed
68 /// pointers into the string given.
72 /// Find the location of a US phone number:
75 /// # use regex::Regex;
76 /// let re = match Regex::new("[0-9]{3}-[0-9]{3}-[0-9]{4}") {
78 /// Err(err) => panic!("{}", err),
80 /// assert_eq!(re.find("phone: 111-222-3333"), Some((7, 19)));
83 /// You can also use the `regex!` macro to compile a regular expression when
84 /// you compile your program:
87 /// #![feature(phase)]
88 /// extern crate regex;
89 /// #[phase(plugin)] extern crate regex_macros;
92 /// let re = regex!(r"\d+");
93 /// assert_eq!(re.find("123 abc"), Some((0, 3)));
97 /// Given an incorrect regular expression, `regex!` will cause the Rust
98 /// compiler to produce a compile time error.
99 /// Note that `regex!` will compile the expression to native Rust code, which
100 /// makes it much faster when searching text.
101 /// More details about the `regex!` macro can be found in the `regex` crate
105 // The representation of `Regex` is exported to support the `regex!`
106 // syntax extension. Do not rely on it.
108 // See the comments for the `program` module in `lib.rs` for a more
109 // detailed explanation for what `regex!` requires.
118 pub struct ExDynamic {
120 names: Vec<Option<String>>,
126 pub struct ExNative {
128 pub original: &'static str,
130 pub names: &'static &'static [Option<&'static str>],
132 pub prog: fn(MatchKind, &str, uint, uint) -> Vec<Option<uint>>
135 impl Clone for ExNative {
136 fn clone(&self) -> ExNative { *self }
139 impl fmt::Show for Regex {
140 /// Shows the original regular expression.
141 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
142 write!(f, "{}", self.as_str())
147 /// Compiles a dynamic regular expression. Once compiled, it can be
148 /// used repeatedly to search, split or replace text in a string.
150 /// When possible, you should prefer the `regex!` macro since it is
151 /// safer and always faster.
153 /// If an invalid expression is given, then an error is returned.
154 pub fn new(re: &str) -> Result<Regex, parse::Error> {
155 let ast = try!(parse::parse(re));
156 let (prog, names) = Program::new(ast);
157 Ok(Dynamic(ExDynamic {
158 original: re.to_string(),
164 /// Returns true if and only if the regex matches the string given.
168 /// Test if some text contains at least one word with exactly 13
172 /// # #![feature(phase)]
173 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
175 /// let text = "I categorically deny having triskaidekaphobia.";
176 /// let matched = regex!(r"\b\w{13}\b").is_match(text);
177 /// assert!(matched);
180 pub fn is_match(&self, text: &str) -> bool {
181 has_match(&exec(self, Exists, text))
184 /// Returns the start and end byte range of the leftmost-first match in
185 /// `text`. If no match exists, then `None` is returned.
187 /// Note that this should only be used if you want to discover the position
188 /// of the match. Testing the existence of a match is faster if you use
193 /// Find the start and end location of the first word with exactly 13
197 /// # #![feature(phase)]
198 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
200 /// let text = "I categorically deny having triskaidekaphobia.";
201 /// let pos = regex!(r"\b\w{13}\b").find(text);
202 /// assert_eq!(pos, Some((2, 15)));
205 pub fn find(&self, text: &str) -> Option<(uint, uint)> {
206 let caps = exec(self, Location, text);
207 if has_match(&caps) {
208 Some((caps[0].unwrap(), caps[1].unwrap()))
214 /// Returns an iterator for each successive non-overlapping match in
215 /// `text`, returning the start and end byte indices with respect to
220 /// Find the start and end location of every word with exactly 13
224 /// # #![feature(phase)]
225 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
227 /// let text = "Retroactively relinquishing remunerations is reprehensible.";
228 /// for pos in regex!(r"\b\w{13}\b").find_iter(text) {
229 /// println!("{}", pos);
238 pub fn find_iter<'r, 't>(&'r self, text: &'t str) -> FindMatches<'r, 't> {
247 /// Returns the capture groups corresponding to the leftmost-first
248 /// match in `text`. Capture group `0` always corresponds to the entire
249 /// match. If no match is found, then `None` is returned.
251 /// You should only use `captures` if you need access to submatches.
252 /// Otherwise, `find` is faster for discovering the location of the overall
257 /// Say you have some text with movie names and their release years,
258 /// like "'Citizen Kane' (1941)". It'd be nice if we could search for text
259 /// looking like that, while also extracting the movie name and its release
263 /// # #![feature(phase)]
264 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
266 /// let re = regex!(r"'([^']+)'\s+\((\d{4})\)");
267 /// let text = "Not my favorite movie: 'Citizen Kane' (1941).";
268 /// let caps = re.captures(text).unwrap();
269 /// assert_eq!(caps.at(1), "Citizen Kane");
270 /// assert_eq!(caps.at(2), "1941");
271 /// assert_eq!(caps.at(0), "'Citizen Kane' (1941)");
275 /// Note that the full match is at capture group `0`. Each subsequent
276 /// capture group is indexed by the order of its opening `(`.
278 /// We can make this example a bit clearer by using *named* capture groups:
281 /// # #![feature(phase)]
282 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
284 /// let re = regex!(r"'(?P<title>[^']+)'\s+\((?P<year>\d{4})\)");
285 /// let text = "Not my favorite movie: 'Citizen Kane' (1941).";
286 /// let caps = re.captures(text).unwrap();
287 /// assert_eq!(caps.name("title"), "Citizen Kane");
288 /// assert_eq!(caps.name("year"), "1941");
289 /// assert_eq!(caps.at(0), "'Citizen Kane' (1941)");
293 /// Here we name the capture groups, which we can access with the `name`
294 /// method. Note that the named capture groups are still accessible with
297 /// The `0`th capture group is always unnamed, so it must always be
298 /// accessed with `at(0)`.
299 pub fn captures<'t>(&self, text: &'t str) -> Option<Captures<'t>> {
300 let caps = exec(self, Submatches, text);
301 Captures::new(self, text, caps)
304 /// Returns an iterator over all the non-overlapping capture groups matched
305 /// in `text`. This is operationally the same as `find_iter` (except it
306 /// yields information about submatches).
310 /// We can use this to find all movie titles and their release years in
311 /// some text, where the movie is formatted like "'Title' (xxxx)":
314 /// # #![feature(phase)]
315 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
317 /// let re = regex!(r"'(?P<title>[^']+)'\s+\((?P<year>\d{4})\)");
318 /// let text = "'Citizen Kane' (1941), 'The Wizard of Oz' (1939), 'M' (1931).";
319 /// for caps in re.captures_iter(text) {
320 /// println!("Movie: {}, Released: {}", caps.name("title"), caps.name("year"));
323 /// // Movie: Citizen Kane, Released: 1941
324 /// // Movie: The Wizard of Oz, Released: 1939
325 /// // Movie: M, Released: 1931
328 pub fn captures_iter<'r, 't>(&'r self, text: &'t str)
329 -> FindCaptures<'r, 't> {
338 /// Returns an iterator of substrings of `text` delimited by a match
339 /// of the regular expression.
340 /// Namely, each element of the iterator corresponds to text that *isn't*
341 /// matched by the regular expression.
343 /// This method will *not* copy the text given.
347 /// To split a string delimited by arbitrary amounts of spaces or tabs:
350 /// # #![feature(phase)]
351 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
353 /// let re = regex!(r"[ \t]+");
354 /// let fields: Vec<&str> = re.split("a b \t c\td e").collect();
355 /// assert_eq!(fields, vec!("a", "b", "c", "d", "e"));
358 pub fn split<'r, 't>(&'r self, text: &'t str) -> RegexSplits<'r, 't> {
360 finder: self.find_iter(text),
365 /// Returns an iterator of at most `limit` substrings of `text` delimited
366 /// by a match of the regular expression. (A `limit` of `0` will return no
368 /// Namely, each element of the iterator corresponds to text that *isn't*
369 /// matched by the regular expression.
370 /// The remainder of the string that is not split will be the last element
373 /// This method will *not* copy the text given.
377 /// Get the first two words in some text:
380 /// # #![feature(phase)]
381 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
383 /// let re = regex!(r"\W+");
384 /// let fields: Vec<&str> = re.splitn("Hey! How are you?", 3).collect();
385 /// assert_eq!(fields, vec!("Hey", "How", "are you?"));
388 pub fn splitn<'r, 't>(&'r self, text: &'t str, limit: uint)
389 -> RegexSplitsN<'r, 't> {
391 splits: self.split(text),
397 /// Replaces the leftmost-first match with the replacement provided.
398 /// The replacement can be a regular string (where `$N` and `$name` are
399 /// expanded to match capture groups) or a function that takes the matches'
400 /// `Captures` and returns the replaced string.
402 /// If no match is found, then a copy of the string is returned unchanged.
406 /// Note that this function is polymorphic with respect to the replacement.
407 /// In typical usage, this can just be a normal string:
410 /// # #![feature(phase)]
411 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
413 /// let re = regex!("[^01]+");
414 /// assert_eq!(re.replace("1078910", "").as_slice(), "1010");
418 /// But anything satisfying the `Replacer` trait will work. For example,
419 /// a closure of type `|&Captures| -> String` provides direct access to the
420 /// captures corresponding to a match. This allows one to access
421 /// submatches easily:
424 /// # #![feature(phase)]
425 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
426 /// # use regex::Captures; fn main() {
427 /// let re = regex!(r"([^,\s]+),\s+(\S+)");
428 /// let result = re.replace("Springsteen, Bruce", |caps: &Captures| {
429 /// format!("{} {}", caps.at(2), caps.at(1))
431 /// assert_eq!(result.as_slice(), "Bruce Springsteen");
435 /// But this is a bit cumbersome to use all the time. Instead, a simple
436 /// syntax is supported that expands `$name` into the corresponding capture
437 /// group. Here's the last example, but using this expansion technique
438 /// with named capture groups:
441 /// # #![feature(phase)]
442 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
444 /// let re = regex!(r"(?P<last>[^,\s]+),\s+(?P<first>\S+)");
445 /// let result = re.replace("Springsteen, Bruce", "$first $last");
446 /// assert_eq!(result.as_slice(), "Bruce Springsteen");
450 /// Note that using `$2` instead of `$first` or `$1` instead of `$last`
451 /// would produce the same result. To write a literal `$` use `$$`.
453 /// Finally, sometimes you just want to replace a literal string with no
454 /// submatch expansion. This can be done by wrapping a string with
458 /// # #![feature(phase)]
459 /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
461 /// use regex::NoExpand;
463 /// let re = regex!(r"(?P<last>[^,\s]+),\s+(\S+)");
464 /// let result = re.replace("Springsteen, Bruce", NoExpand("$2 $last"));
465 /// assert_eq!(result.as_slice(), "$2 $last");
468 pub fn replace<R: Replacer>(&self, text: &str, rep: R) -> String {
469 self.replacen(text, 1, rep)
472 /// Replaces all non-overlapping matches in `text` with the
473 /// replacement provided. This is the same as calling `replacen` with
474 /// `limit` set to `0`.
476 /// See the documentation for `replace` for details on how to access
477 /// submatches in the replacement string.
478 pub fn replace_all<R: Replacer>(&self, text: &str, rep: R) -> String {
479 self.replacen(text, 0, rep)
482 /// Replaces at most `limit` non-overlapping matches in `text` with the
483 /// replacement provided. If `limit` is 0, then all non-overlapping matches
486 /// See the documentation for `replace` for details on how to access
487 /// submatches in the replacement string.
488 pub fn replacen<R: Replacer>
489 (&self, text: &str, limit: uint, mut rep: R) -> String {
490 let mut new = String::with_capacity(text.len());
491 let mut last_match = 0u;
493 for (i, cap) in self.captures_iter(text).enumerate() {
494 // It'd be nicer to use the 'take' iterator instead, but it seemed
495 // awkward given that '0' => no limit.
496 if limit > 0 && i >= limit {
500 let (s, e) = cap.pos(0).unwrap(); // captures only reports matches
501 new.push_str(text.slice(last_match, s));
502 new.push_str(rep.reg_replace(&cap).as_slice());
505 new.push_str(text.slice(last_match, text.len()));
509 /// Returns the original string of this regex.
510 pub fn as_str<'a>(&'a self) -> &'a str {
512 Dynamic(ExDynamic { ref original, .. }) => original.as_slice(),
513 Native(ExNative { ref original, .. }) => original.as_slice(),
519 pub fn names_iter<'a>(&'a self) -> NamesIter<'a> {
521 Native(ref n) => NamesIterNative(n.names.iter()),
522 Dynamic(ref d) => NamesIterDynamic(d.names.iter())
526 fn names_len(&self) -> uint {
528 Native(ref n) => n.names.len(),
529 Dynamic(ref d) => d.names.len()
535 pub enum NamesIter<'a> {
536 NamesIterNative(::std::slice::Items<'a, Option<&'static str>>),
537 NamesIterDynamic(::std::slice::Items<'a, Option<String>>)
540 impl<'a> Iterator<Option<String>> for NamesIter<'a> {
541 fn next(&mut self) -> Option<Option<String>> {
543 NamesIterNative(ref mut i) => i.next().map(|x| x.map(|s| s.to_string())),
544 NamesIterDynamic(ref mut i) => i.next().map(|x| x.as_ref().map(|s| s.to_string())),
549 /// NoExpand indicates literal string replacement.
551 /// It can be used with `replace` and `replace_all` to do a literal
552 /// string replacement without expanding `$name` to their corresponding
555 /// `'r` is the lifetime of the literal text.
556 pub struct NoExpand<'t>(pub &'t str);
558 /// Replacer describes types that can be used to replace matches in a string.
560 /// Returns a possibly owned string that is used to replace the match
561 /// corresponding the the `caps` capture group.
563 /// The `'a` lifetime refers to the lifetime of a borrowed string when
564 /// a new owned string isn't needed (e.g., for `NoExpand`).
565 fn reg_replace<'a>(&'a mut self, caps: &Captures) -> MaybeOwned<'a>;
568 impl<'t> Replacer for NoExpand<'t> {
569 fn reg_replace<'a>(&'a mut self, _: &Captures) -> MaybeOwned<'a> {
570 let NoExpand(s) = *self;
575 impl<'t> Replacer for &'t str {
576 fn reg_replace<'a>(&'a mut self, caps: &Captures) -> MaybeOwned<'a> {
577 Owned(caps.expand(*self))
581 impl<'t> Replacer for |&Captures|: 't -> String {
582 fn reg_replace<'a>(&'a mut self, caps: &Captures) -> MaybeOwned<'a> {
587 /// Yields all substrings delimited by a regular expression match.
589 /// `'r` is the lifetime of the compiled expression and `'t` is the lifetime
590 /// of the string being split.
591 pub struct RegexSplits<'r, 't> {
592 finder: FindMatches<'r, 't>,
596 impl<'r, 't> Iterator<&'t str> for RegexSplits<'r, 't> {
597 fn next(&mut self) -> Option<&'t str> {
598 let text = self.finder.search;
599 match self.finder.next() {
601 if self.last >= text.len() {
604 let s = text.slice(self.last, text.len());
605 self.last = text.len();
610 let matched = text.slice(self.last, s);
618 /// Yields at most `N` substrings delimited by a regular expression match.
620 /// The last substring will be whatever remains after splitting.
622 /// `'r` is the lifetime of the compiled expression and `'t` is the lifetime
623 /// of the string being split.
624 pub struct RegexSplitsN<'r, 't> {
625 splits: RegexSplits<'r, 't>,
630 impl<'r, 't> Iterator<&'t str> for RegexSplitsN<'r, 't> {
631 fn next(&mut self) -> Option<&'t str> {
632 let text = self.splits.finder.search;
633 if self.cur >= self.limit {
637 if self.cur >= self.limit {
638 Some(text.slice(self.splits.last, text.len()))
646 /// Captures represents a group of captured strings for a single match.
648 /// The 0th capture always corresponds to the entire match. Each subsequent
649 /// index corresponds to the next capture group in the regex.
650 /// If a capture group is named, then the matched string is *also* available
651 /// via the `name` method. (Note that the 0th capture is always unnamed and so
652 /// must be accessed with the `at` method.)
654 /// Positions returned from a capture group are always byte indices.
656 /// `'t` is the lifetime of the matched text.
657 pub struct Captures<'t> {
660 named: Option<HashMap<String, uint>>,
663 impl<'t> Captures<'t> {
664 #[allow(experimental)]
665 fn new(re: &Regex, search: &'t str, locs: CaptureLocs)
666 -> Option<Captures<'t>> {
667 if !has_match(&locs) {
672 if re.names_len() == 0 {
675 let mut named = HashMap::new();
676 for (i, name) in re.names_iter().enumerate() {
680 named.insert(name, i);
693 /// Returns the start and end positions of the Nth capture group.
694 /// Returns `None` if `i` is not a valid capture group or if the capture
695 /// group did not match anything.
696 /// The positions returned are *always* byte indices with respect to the
697 /// original string matched.
698 pub fn pos(&self, i: uint) -> Option<(uint, uint)> {
699 let (s, e) = (i * 2, i * 2 + 1);
700 if e >= self.locs.len() || self.locs[s].is_none() {
701 // VM guarantees that each pair of locations are both Some or None.
704 Some((self.locs[s].unwrap(), self.locs[e].unwrap()))
707 /// Returns the matched string for the capture group `i`.
708 /// If `i` isn't a valid capture group or didn't match anything, then the
709 /// empty string is returned.
710 pub fn at(&self, i: uint) -> &'t str {
714 self.text.slice(s, e)
719 /// Returns the matched string for the capture group named `name`.
720 /// If `name` isn't a valid capture group or didn't match anything, then
721 /// the empty string is returned.
722 pub fn name(&self, name: &str) -> &'t str {
726 match h.find_equiv(name) {
728 Some(i) => self.at(*i),
734 /// Creates an iterator of all the capture groups in order of appearance
735 /// in the regular expression.
736 pub fn iter(&'t self) -> SubCaptures<'t> {
737 SubCaptures { idx: 0, caps: self, }
740 /// Creates an iterator of all the capture group positions in order of
741 /// appearance in the regular expression. Positions are byte indices
742 /// in terms of the original string matched.
743 pub fn iter_pos(&'t self) -> SubCapturesPos<'t> {
744 SubCapturesPos { idx: 0, caps: self, }
747 /// Expands all instances of `$name` in `text` to the corresponding capture
750 /// `name` may be an integer corresponding to the index of the
751 /// capture group (counted by order of opening parenthesis where `0` is the
752 /// entire match) or it can be a name (consisting of letters, digits or
753 /// underscores) corresponding to a named capture group.
755 /// If `name` isn't a valid capture group (whether the name doesn't exist or
756 /// isn't a valid index), then it is replaced with the empty string.
758 /// To write a literal `$` use `$$`.
759 pub fn expand(&self, text: &str) -> String {
760 // How evil can you get?
761 // FIXME: Don't use regexes for this. It's completely unnecessary.
762 let re = Regex::new(r"(^|[^$]|\b)\$(\w+)").unwrap();
763 let text = re.replace_all(text, |refs: &Captures| -> String {
764 let (pre, name) = (refs.at(1), refs.at(2));
766 match from_str::<uint>(name.as_slice()) {
767 None => self.name(name).to_string(),
768 Some(i) => self.at(i).to_string(),
771 let re = Regex::new(r"\$\$").unwrap();
772 re.replace_all(text.as_slice(), NoExpand("$"))
775 /// Returns the number of captured groups.
777 pub fn len(&self) -> uint { self.locs.len() / 2 }
779 /// Returns if there are no captured groups.
781 pub fn is_empty(&self) -> bool { self.len() == 0 }
784 /// An iterator over capture groups for a particular match of a regular
787 /// `'t` is the lifetime of the matched text.
788 pub struct SubCaptures<'t> {
790 caps: &'t Captures<'t>,
793 impl<'t> Iterator<&'t str> for SubCaptures<'t> {
794 fn next(&mut self) -> Option<&'t str> {
795 if self.idx < self.caps.len() {
797 Some(self.caps.at(self.idx - 1))
804 /// An iterator over capture group positions for a particular match of a
805 /// regular expression.
807 /// Positions are byte indices in terms of the original string matched.
809 /// `'t` is the lifetime of the matched text.
810 pub struct SubCapturesPos<'t> {
812 caps: &'t Captures<'t>,
815 impl<'t> Iterator<Option<(uint, uint)>> for SubCapturesPos<'t> {
816 fn next(&mut self) -> Option<Option<(uint, uint)>> {
817 if self.idx < self.caps.len() {
819 Some(self.caps.pos(self.idx - 1))
826 /// An iterator that yields all non-overlapping capture groups matching a
827 /// particular regular expression.
829 /// The iterator stops when no more matches can be found.
831 /// `'r` is the lifetime of the compiled expression and `'t` is the lifetime
832 /// of the matched string.
833 pub struct FindCaptures<'r, 't> {
836 last_match: Option<uint>,
840 impl<'r, 't> Iterator<Captures<'t>> for FindCaptures<'r, 't> {
841 fn next(&mut self) -> Option<Captures<'t>> {
842 if self.last_end > self.search.len() {
846 let caps = exec_slice(self.re, Submatches, self.search,
847 self.last_end, self.search.len());
849 if !has_match(&caps) {
852 (caps[0].unwrap(), caps[1].unwrap())
855 // Don't accept empty matches immediately following a match.
856 // i.e., no infinite loops please.
857 if e == s && Some(self.last_end) == self.last_match {
862 self.last_match = Some(self.last_end);
863 Captures::new(self.re, self.search, caps)
867 /// An iterator over all non-overlapping matches for a particular string.
869 /// The iterator yields a tuple of integers corresponding to the start and end
870 /// of the match. The indices are byte offsets. The iterator stops when no more
871 /// matches can be found.
873 /// `'r` is the lifetime of the compiled expression and `'t` is the lifetime
874 /// of the matched string.
875 pub struct FindMatches<'r, 't> {
878 last_match: Option<uint>,
882 impl<'r, 't> Iterator<(uint, uint)> for FindMatches<'r, 't> {
883 fn next(&mut self) -> Option<(uint, uint)> {
884 if self.last_end > self.search.len() {
888 let caps = exec_slice(self.re, Location, self.search,
889 self.last_end, self.search.len());
891 if !has_match(&caps) {
894 (caps[0].unwrap(), caps[1].unwrap())
897 // Don't accept empty matches immediately following a match.
898 // i.e., no infinite loops please.
899 if e == s && Some(self.last_end) == self.last_match {
904 self.last_match = Some(self.last_end);
909 fn exec(re: &Regex, which: MatchKind, input: &str) -> CaptureLocs {
910 exec_slice(re, which, input, 0, input.len())
913 fn exec_slice(re: &Regex, which: MatchKind,
914 input: &str, s: uint, e: uint) -> CaptureLocs {
916 Dynamic(ExDynamic { ref prog, .. }) => vm::run(which, prog, input, s, e),
917 Native(ExNative { prog, .. }) => prog(which, input, s, e),
922 fn has_match(caps: &CaptureLocs) -> bool {
923 caps.len() >= 2 && caps[0].is_some() && caps[1].is_some()