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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. | |
4 | // | |
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. | |
10 | ||
11 | // This is pretty much entirely stolen from TreeSet, since BTreeMap has an identical interface | |
12 | // to TreeMap | |
13 | ||
1a4d82fc | 14 | use core::cmp::Ordering::{self, Less, Greater, Equal}; |
85aaf69f | 15 | use core::fmt::Debug; |
1a4d82fc | 16 | use core::fmt; |
9346a6ac | 17 | use core::iter::{Peekable, Map, FromIterator}; |
1a4d82fc JJ |
18 | use core::ops::{BitOr, BitAnd, BitXor, Sub}; |
19 | ||
85aaf69f | 20 | use borrow::Borrow; |
1a4d82fc | 21 | use btree_map::{BTreeMap, Keys}; |
e9174d1e | 22 | use super::Recover; |
85aaf69f | 23 | use Bound; |
1a4d82fc JJ |
24 | |
25 | // FIXME(conventions): implement bounded iterators | |
26 | ||
27 | /// A set based on a B-Tree. | |
28 | /// | |
29 | /// See BTreeMap's documentation for a detailed discussion of this collection's performance | |
30 | /// benefits and drawbacks. | |
c34b1796 AL |
31 | /// |
32 | /// It is a logic error for an item to be modified in such a way that the item's ordering relative | |
33 | /// to any other item, as determined by the `Ord` trait, changes while it is in the set. This is | |
34 | /// normally only possible through `Cell`, `RefCell`, global state, I/O, or unsafe code. | |
1a4d82fc | 35 | #[derive(Clone, Hash, PartialEq, Eq, Ord, PartialOrd)] |
85aaf69f | 36 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 | 37 | pub struct BTreeSet<T> { |
1a4d82fc JJ |
38 | map: BTreeMap<T, ()>, |
39 | } | |
40 | ||
41 | /// An iterator over a BTreeSet's items. | |
85aaf69f | 42 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 43 | pub struct Iter<'a, T: 'a> { |
92a42be0 | 44 | iter: Keys<'a, T, ()>, |
1a4d82fc JJ |
45 | } |
46 | ||
47 | /// An owning iterator over a BTreeSet's items. | |
85aaf69f | 48 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 49 | pub struct IntoIter<T> { |
92a42be0 | 50 | iter: Map<::btree_map::IntoIter<T, ()>, fn((T, ())) -> T>, |
85aaf69f SL |
51 | } |
52 | ||
53 | /// An iterator over a sub-range of BTreeSet's items. | |
54 | pub struct Range<'a, T: 'a> { | |
92a42be0 | 55 | iter: Map<::btree_map::Range<'a, T, ()>, fn((&'a T, &'a ())) -> &'a T>, |
1a4d82fc JJ |
56 | } |
57 | ||
58 | /// A lazy iterator producing elements in the set difference (in-order). | |
85aaf69f | 59 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 | 60 | pub struct Difference<'a, T: 'a> { |
85aaf69f SL |
61 | a: Peekable<Iter<'a, T>>, |
62 | b: Peekable<Iter<'a, T>>, | |
1a4d82fc JJ |
63 | } |
64 | ||
65 | /// A lazy iterator producing elements in the set symmetric difference (in-order). | |
85aaf69f | 66 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 | 67 | pub struct SymmetricDifference<'a, T: 'a> { |
85aaf69f SL |
68 | a: Peekable<Iter<'a, T>>, |
69 | b: Peekable<Iter<'a, T>>, | |
1a4d82fc JJ |
70 | } |
71 | ||
72 | /// A lazy iterator producing elements in the set intersection (in-order). | |
85aaf69f | 73 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 | 74 | pub struct Intersection<'a, T: 'a> { |
85aaf69f SL |
75 | a: Peekable<Iter<'a, T>>, |
76 | b: Peekable<Iter<'a, T>>, | |
1a4d82fc JJ |
77 | } |
78 | ||
79 | /// A lazy iterator producing elements in the set union (in-order). | |
85aaf69f | 80 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 | 81 | pub struct Union<'a, T: 'a> { |
85aaf69f SL |
82 | a: Peekable<Iter<'a, T>>, |
83 | b: Peekable<Iter<'a, T>>, | |
1a4d82fc JJ |
84 | } |
85 | ||
86 | impl<T: Ord> BTreeSet<T> { | |
87 | /// Makes a new BTreeSet with a reasonable choice of B. | |
88 | /// | |
89 | /// # Examples | |
90 | /// | |
91 | /// ``` | |
92a42be0 | 92 | /// # #![allow(unused_mut)] |
1a4d82fc JJ |
93 | /// use std::collections::BTreeSet; |
94 | /// | |
85aaf69f | 95 | /// let mut set: BTreeSet<i32> = BTreeSet::new(); |
1a4d82fc | 96 | /// ``` |
85aaf69f | 97 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
98 | pub fn new() -> BTreeSet<T> { |
99 | BTreeSet { map: BTreeMap::new() } | |
100 | } | |
101 | ||
102 | /// Makes a new BTreeSet with the given B. | |
103 | /// | |
104 | /// B cannot be less than 2. | |
62682a34 | 105 | #[unstable(feature = "btree_b", |
e9174d1e SL |
106 | reason = "probably want this to be on the type, eventually", |
107 | issue = "27795")] | |
92a42be0 | 108 | #[rustc_deprecated(since = "1.4.0", reason = "niche API")] |
e9174d1e | 109 | #[allow(deprecated)] |
85aaf69f | 110 | pub fn with_b(b: usize) -> BTreeSet<T> { |
1a4d82fc JJ |
111 | BTreeSet { map: BTreeMap::with_b(b) } |
112 | } | |
113 | } | |
114 | ||
115 | impl<T> BTreeSet<T> { | |
116 | /// Gets an iterator over the BTreeSet's contents. | |
117 | /// | |
118 | /// # Examples | |
119 | /// | |
120 | /// ``` | |
121 | /// use std::collections::BTreeSet; | |
122 | /// | |
85aaf69f | 123 | /// let set: BTreeSet<usize> = [1, 2, 3, 4].iter().cloned().collect(); |
1a4d82fc JJ |
124 | /// |
125 | /// for x in set.iter() { | |
126 | /// println!("{}", x); | |
127 | /// } | |
128 | /// | |
62682a34 | 129 | /// let v: Vec<_> = set.iter().cloned().collect(); |
c34b1796 | 130 | /// assert_eq!(v, [1, 2, 3, 4]); |
1a4d82fc | 131 | /// ``` |
85aaf69f | 132 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
133 | pub fn iter(&self) -> Iter<T> { |
134 | Iter { iter: self.map.keys() } | |
135 | } | |
1a4d82fc JJ |
136 | } |
137 | ||
85aaf69f SL |
138 | impl<T: Ord> BTreeSet<T> { |
139 | /// Constructs a double-ended iterator over a sub-range of elements in the set, starting | |
140 | /// at min, and ending at max. If min is `Unbounded`, then it will be treated as "negative | |
141 | /// infinity", and if max is `Unbounded`, then it will be treated as "positive infinity". | |
142 | /// Thus range(Unbounded, Unbounded) will yield the whole collection. | |
143 | /// | |
144 | /// # Examples | |
145 | /// | |
146 | /// ``` | |
c1a9b12d SL |
147 | /// #![feature(btree_range, collections_bound)] |
148 | /// | |
85aaf69f SL |
149 | /// use std::collections::BTreeSet; |
150 | /// use std::collections::Bound::{Included, Unbounded}; | |
151 | /// | |
152 | /// let mut set = BTreeSet::new(); | |
153 | /// set.insert(3); | |
154 | /// set.insert(5); | |
155 | /// set.insert(8); | |
156 | /// for &elem in set.range(Included(&4), Included(&8)) { | |
157 | /// println!("{}", elem); | |
158 | /// } | |
159 | /// assert_eq!(Some(&5), set.range(Included(&4), Unbounded).next()); | |
160 | /// ``` | |
62682a34 | 161 | #[unstable(feature = "btree_range", |
e9174d1e SL |
162 | reason = "matches collection reform specification, waiting for dust to settle", |
163 | issue = "27787")] | |
92a42be0 SL |
164 | pub fn range<'a, Min: ?Sized + Ord = T, Max: ?Sized + Ord = T>(&'a self, |
165 | min: Bound<&Min>, | |
e9174d1e | 166 | max: Bound<&Max>) |
92a42be0 SL |
167 | -> Range<'a, T> |
168 | where T: Borrow<Min> + Borrow<Max> | |
e9174d1e | 169 | { |
92a42be0 SL |
170 | fn first<A, B>((a, _): (A, B)) -> A { |
171 | a | |
172 | } | |
85aaf69f SL |
173 | let first: fn((&'a T, &'a ())) -> &'a T = first; // coerce to fn pointer |
174 | ||
175 | Range { iter: self.map.range(min, max).map(first) } | |
176 | } | |
177 | } | |
178 | ||
1a4d82fc JJ |
179 | impl<T: Ord> BTreeSet<T> { |
180 | /// Visits the values representing the difference, in ascending order. | |
181 | /// | |
182 | /// # Examples | |
183 | /// | |
184 | /// ``` | |
185 | /// use std::collections::BTreeSet; | |
186 | /// | |
187 | /// let mut a = BTreeSet::new(); | |
85aaf69f SL |
188 | /// a.insert(1); |
189 | /// a.insert(2); | |
1a4d82fc JJ |
190 | /// |
191 | /// let mut b = BTreeSet::new(); | |
85aaf69f SL |
192 | /// b.insert(2); |
193 | /// b.insert(3); | |
1a4d82fc | 194 | /// |
62682a34 | 195 | /// let diff: Vec<_> = a.difference(&b).cloned().collect(); |
c34b1796 | 196 | /// assert_eq!(diff, [1]); |
1a4d82fc | 197 | /// ``` |
85aaf69f | 198 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 199 | pub fn difference<'a>(&'a self, other: &'a BTreeSet<T>) -> Difference<'a, T> { |
92a42be0 SL |
200 | Difference { |
201 | a: self.iter().peekable(), | |
202 | b: other.iter().peekable(), | |
203 | } | |
1a4d82fc JJ |
204 | } |
205 | ||
206 | /// Visits the values representing the symmetric difference, in ascending order. | |
207 | /// | |
208 | /// # Examples | |
209 | /// | |
210 | /// ``` | |
211 | /// use std::collections::BTreeSet; | |
212 | /// | |
213 | /// let mut a = BTreeSet::new(); | |
85aaf69f SL |
214 | /// a.insert(1); |
215 | /// a.insert(2); | |
1a4d82fc JJ |
216 | /// |
217 | /// let mut b = BTreeSet::new(); | |
85aaf69f SL |
218 | /// b.insert(2); |
219 | /// b.insert(3); | |
1a4d82fc | 220 | /// |
62682a34 | 221 | /// let sym_diff: Vec<_> = a.symmetric_difference(&b).cloned().collect(); |
c34b1796 | 222 | /// assert_eq!(sym_diff, [1, 3]); |
1a4d82fc | 223 | /// ``` |
85aaf69f | 224 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 SL |
225 | pub fn symmetric_difference<'a>(&'a self, |
226 | other: &'a BTreeSet<T>) | |
227 | -> SymmetricDifference<'a, T> { | |
228 | SymmetricDifference { | |
229 | a: self.iter().peekable(), | |
230 | b: other.iter().peekable(), | |
231 | } | |
1a4d82fc JJ |
232 | } |
233 | ||
234 | /// Visits the values representing the intersection, in ascending order. | |
235 | /// | |
236 | /// # Examples | |
237 | /// | |
238 | /// ``` | |
239 | /// use std::collections::BTreeSet; | |
240 | /// | |
241 | /// let mut a = BTreeSet::new(); | |
85aaf69f SL |
242 | /// a.insert(1); |
243 | /// a.insert(2); | |
1a4d82fc JJ |
244 | /// |
245 | /// let mut b = BTreeSet::new(); | |
85aaf69f SL |
246 | /// b.insert(2); |
247 | /// b.insert(3); | |
1a4d82fc | 248 | /// |
62682a34 | 249 | /// let intersection: Vec<_> = a.intersection(&b).cloned().collect(); |
c34b1796 | 250 | /// assert_eq!(intersection, [2]); |
1a4d82fc | 251 | /// ``` |
85aaf69f | 252 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 SL |
253 | pub fn intersection<'a>(&'a self, other: &'a BTreeSet<T>) -> Intersection<'a, T> { |
254 | Intersection { | |
255 | a: self.iter().peekable(), | |
256 | b: other.iter().peekable(), | |
257 | } | |
1a4d82fc JJ |
258 | } |
259 | ||
260 | /// Visits the values representing the union, in ascending order. | |
261 | /// | |
262 | /// # Examples | |
263 | /// | |
264 | /// ``` | |
265 | /// use std::collections::BTreeSet; | |
266 | /// | |
267 | /// let mut a = BTreeSet::new(); | |
85aaf69f | 268 | /// a.insert(1); |
1a4d82fc JJ |
269 | /// |
270 | /// let mut b = BTreeSet::new(); | |
85aaf69f | 271 | /// b.insert(2); |
1a4d82fc | 272 | /// |
62682a34 | 273 | /// let union: Vec<_> = a.union(&b).cloned().collect(); |
c34b1796 | 274 | /// assert_eq!(union, [1, 2]); |
1a4d82fc | 275 | /// ``` |
85aaf69f | 276 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 277 | pub fn union<'a>(&'a self, other: &'a BTreeSet<T>) -> Union<'a, T> { |
92a42be0 SL |
278 | Union { |
279 | a: self.iter().peekable(), | |
280 | b: other.iter().peekable(), | |
281 | } | |
1a4d82fc JJ |
282 | } |
283 | ||
9346a6ac | 284 | /// Returns the number of elements in the set. |
1a4d82fc JJ |
285 | /// |
286 | /// # Examples | |
287 | /// | |
288 | /// ``` | |
289 | /// use std::collections::BTreeSet; | |
290 | /// | |
291 | /// let mut v = BTreeSet::new(); | |
292 | /// assert_eq!(v.len(), 0); | |
85aaf69f | 293 | /// v.insert(1); |
1a4d82fc JJ |
294 | /// assert_eq!(v.len(), 1); |
295 | /// ``` | |
85aaf69f | 296 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 SL |
297 | pub fn len(&self) -> usize { |
298 | self.map.len() | |
299 | } | |
1a4d82fc | 300 | |
9346a6ac | 301 | /// Returns true if the set contains no elements. |
1a4d82fc JJ |
302 | /// |
303 | /// # Examples | |
304 | /// | |
305 | /// ``` | |
306 | /// use std::collections::BTreeSet; | |
307 | /// | |
308 | /// let mut v = BTreeSet::new(); | |
309 | /// assert!(v.is_empty()); | |
85aaf69f | 310 | /// v.insert(1); |
1a4d82fc JJ |
311 | /// assert!(!v.is_empty()); |
312 | /// ``` | |
85aaf69f | 313 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 SL |
314 | pub fn is_empty(&self) -> bool { |
315 | self.len() == 0 | |
316 | } | |
1a4d82fc JJ |
317 | |
318 | /// Clears the set, removing all values. | |
319 | /// | |
320 | /// # Examples | |
321 | /// | |
322 | /// ``` | |
323 | /// use std::collections::BTreeSet; | |
324 | /// | |
325 | /// let mut v = BTreeSet::new(); | |
85aaf69f | 326 | /// v.insert(1); |
1a4d82fc JJ |
327 | /// v.clear(); |
328 | /// assert!(v.is_empty()); | |
329 | /// ``` | |
85aaf69f | 330 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
331 | pub fn clear(&mut self) { |
332 | self.map.clear() | |
333 | } | |
334 | ||
335 | /// Returns `true` if the set contains a value. | |
336 | /// | |
337 | /// The value may be any borrowed form of the set's value type, | |
338 | /// but the ordering on the borrowed form *must* match the | |
339 | /// ordering on the value type. | |
340 | /// | |
341 | /// # Examples | |
342 | /// | |
343 | /// ``` | |
344 | /// use std::collections::BTreeSet; | |
345 | /// | |
85aaf69f | 346 | /// let set: BTreeSet<_> = [1, 2, 3].iter().cloned().collect(); |
1a4d82fc JJ |
347 | /// assert_eq!(set.contains(&1), true); |
348 | /// assert_eq!(set.contains(&4), false); | |
349 | /// ``` | |
85aaf69f | 350 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 SL |
351 | pub fn contains<Q: ?Sized>(&self, value: &Q) -> bool |
352 | where T: Borrow<Q>, | |
353 | Q: Ord | |
354 | { | |
1a4d82fc JJ |
355 | self.map.contains_key(value) |
356 | } | |
357 | ||
e9174d1e SL |
358 | /// Returns a reference to the value in the set, if any, that is equal to the given value. |
359 | /// | |
360 | /// The value may be any borrowed form of the set's value type, | |
361 | /// but the ordering on the borrowed form *must* match the | |
362 | /// ordering on the value type. | |
363 | #[unstable(feature = "set_recovery", issue = "28050")] | |
92a42be0 SL |
364 | pub fn get<Q: ?Sized>(&self, value: &Q) -> Option<&T> |
365 | where T: Borrow<Q>, | |
366 | Q: Ord | |
367 | { | |
e9174d1e SL |
368 | Recover::get(&self.map, value) |
369 | } | |
370 | ||
1a4d82fc JJ |
371 | /// Returns `true` if the set has no elements in common with `other`. |
372 | /// This is equivalent to checking for an empty intersection. | |
373 | /// | |
374 | /// # Examples | |
375 | /// | |
376 | /// ``` | |
377 | /// use std::collections::BTreeSet; | |
378 | /// | |
85aaf69f SL |
379 | /// let a: BTreeSet<_> = [1, 2, 3].iter().cloned().collect(); |
380 | /// let mut b = BTreeSet::new(); | |
1a4d82fc JJ |
381 | /// |
382 | /// assert_eq!(a.is_disjoint(&b), true); | |
383 | /// b.insert(4); | |
384 | /// assert_eq!(a.is_disjoint(&b), true); | |
385 | /// b.insert(1); | |
386 | /// assert_eq!(a.is_disjoint(&b), false); | |
387 | /// ``` | |
85aaf69f | 388 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
389 | pub fn is_disjoint(&self, other: &BTreeSet<T>) -> bool { |
390 | self.intersection(other).next().is_none() | |
391 | } | |
392 | ||
393 | /// Returns `true` if the set is a subset of another. | |
394 | /// | |
395 | /// # Examples | |
396 | /// | |
397 | /// ``` | |
398 | /// use std::collections::BTreeSet; | |
399 | /// | |
85aaf69f SL |
400 | /// let sup: BTreeSet<_> = [1, 2, 3].iter().cloned().collect(); |
401 | /// let mut set = BTreeSet::new(); | |
1a4d82fc JJ |
402 | /// |
403 | /// assert_eq!(set.is_subset(&sup), true); | |
404 | /// set.insert(2); | |
405 | /// assert_eq!(set.is_subset(&sup), true); | |
406 | /// set.insert(4); | |
407 | /// assert_eq!(set.is_subset(&sup), false); | |
408 | /// ``` | |
85aaf69f | 409 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
410 | pub fn is_subset(&self, other: &BTreeSet<T>) -> bool { |
411 | // Stolen from TreeMap | |
412 | let mut x = self.iter(); | |
413 | let mut y = other.iter(); | |
414 | let mut a = x.next(); | |
415 | let mut b = y.next(); | |
416 | while a.is_some() { | |
417 | if b.is_none() { | |
418 | return false; | |
419 | } | |
420 | ||
421 | let a1 = a.unwrap(); | |
422 | let b1 = b.unwrap(); | |
423 | ||
424 | match b1.cmp(a1) { | |
425 | Less => (), | |
426 | Greater => return false, | |
427 | Equal => a = x.next(), | |
428 | } | |
429 | ||
430 | b = y.next(); | |
431 | } | |
432 | true | |
433 | } | |
434 | ||
435 | /// Returns `true` if the set is a superset of another. | |
436 | /// | |
437 | /// # Examples | |
438 | /// | |
439 | /// ``` | |
440 | /// use std::collections::BTreeSet; | |
441 | /// | |
85aaf69f SL |
442 | /// let sub: BTreeSet<_> = [1, 2].iter().cloned().collect(); |
443 | /// let mut set = BTreeSet::new(); | |
1a4d82fc JJ |
444 | /// |
445 | /// assert_eq!(set.is_superset(&sub), false); | |
446 | /// | |
447 | /// set.insert(0); | |
448 | /// set.insert(1); | |
449 | /// assert_eq!(set.is_superset(&sub), false); | |
450 | /// | |
451 | /// set.insert(2); | |
452 | /// assert_eq!(set.is_superset(&sub), true); | |
453 | /// ``` | |
85aaf69f | 454 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
455 | pub fn is_superset(&self, other: &BTreeSet<T>) -> bool { |
456 | other.is_subset(self) | |
457 | } | |
458 | ||
b039eaaf SL |
459 | /// Adds a value to the set. |
460 | /// | |
461 | /// If the set did not have a value present, `true` is returned. | |
462 | /// | |
463 | /// If the set did have this key present, that value is returned, and the | |
464 | /// entry is not updated. See the [module-level documentation] for more. | |
465 | /// | |
466 | /// [module-level documentation]: index.html#insert-and-complex-keys | |
1a4d82fc JJ |
467 | /// |
468 | /// # Examples | |
469 | /// | |
470 | /// ``` | |
471 | /// use std::collections::BTreeSet; | |
472 | /// | |
473 | /// let mut set = BTreeSet::new(); | |
474 | /// | |
85aaf69f SL |
475 | /// assert_eq!(set.insert(2), true); |
476 | /// assert_eq!(set.insert(2), false); | |
1a4d82fc JJ |
477 | /// assert_eq!(set.len(), 1); |
478 | /// ``` | |
85aaf69f | 479 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
480 | pub fn insert(&mut self, value: T) -> bool { |
481 | self.map.insert(value, ()).is_none() | |
482 | } | |
483 | ||
e9174d1e SL |
484 | /// Adds a value to the set, replacing the existing value, if any, that is equal to the given |
485 | /// one. Returns the replaced value. | |
486 | #[unstable(feature = "set_recovery", issue = "28050")] | |
487 | pub fn replace(&mut self, value: T) -> Option<T> { | |
488 | Recover::replace(&mut self.map, value) | |
489 | } | |
490 | ||
1a4d82fc JJ |
491 | /// Removes a value from the set. Returns `true` if the value was |
492 | /// present in the set. | |
493 | /// | |
494 | /// The value may be any borrowed form of the set's value type, | |
495 | /// but the ordering on the borrowed form *must* match the | |
496 | /// ordering on the value type. | |
497 | /// | |
498 | /// # Examples | |
499 | /// | |
500 | /// ``` | |
501 | /// use std::collections::BTreeSet; | |
502 | /// | |
503 | /// let mut set = BTreeSet::new(); | |
504 | /// | |
85aaf69f | 505 | /// set.insert(2); |
1a4d82fc JJ |
506 | /// assert_eq!(set.remove(&2), true); |
507 | /// assert_eq!(set.remove(&2), false); | |
508 | /// ``` | |
85aaf69f | 509 | #[stable(feature = "rust1", since = "1.0.0")] |
92a42be0 SL |
510 | pub fn remove<Q: ?Sized>(&mut self, value: &Q) -> bool |
511 | where T: Borrow<Q>, | |
512 | Q: Ord | |
513 | { | |
1a4d82fc JJ |
514 | self.map.remove(value).is_some() |
515 | } | |
e9174d1e SL |
516 | |
517 | /// Removes and returns the value in the set, if any, that is equal to the given one. | |
518 | /// | |
519 | /// The value may be any borrowed form of the set's value type, | |
520 | /// but the ordering on the borrowed form *must* match the | |
521 | /// ordering on the value type. | |
522 | #[unstable(feature = "set_recovery", issue = "28050")] | |
92a42be0 SL |
523 | pub fn take<Q: ?Sized>(&mut self, value: &Q) -> Option<T> |
524 | where T: Borrow<Q>, | |
525 | Q: Ord | |
526 | { | |
e9174d1e SL |
527 | Recover::take(&mut self.map, value) |
528 | } | |
1a4d82fc JJ |
529 | } |
530 | ||
85aaf69f | 531 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 532 | impl<T: Ord> FromIterator<T> for BTreeSet<T> { |
92a42be0 | 533 | fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> BTreeSet<T> { |
1a4d82fc JJ |
534 | let mut set = BTreeSet::new(); |
535 | set.extend(iter); | |
536 | set | |
537 | } | |
538 | } | |
539 | ||
85aaf69f SL |
540 | #[stable(feature = "rust1", since = "1.0.0")] |
541 | impl<T> IntoIterator for BTreeSet<T> { | |
542 | type Item = T; | |
543 | type IntoIter = IntoIter<T>; | |
544 | ||
9346a6ac AL |
545 | /// Gets an iterator for moving out the BtreeSet's contents. |
546 | /// | |
547 | /// # Examples | |
548 | /// | |
549 | /// ``` | |
9346a6ac AL |
550 | /// use std::collections::BTreeSet; |
551 | /// | |
552 | /// let set: BTreeSet<usize> = [1, 2, 3, 4].iter().cloned().collect(); | |
553 | /// | |
62682a34 | 554 | /// let v: Vec<_> = set.into_iter().collect(); |
9346a6ac AL |
555 | /// assert_eq!(v, [1, 2, 3, 4]); |
556 | /// ``` | |
85aaf69f | 557 | fn into_iter(self) -> IntoIter<T> { |
92a42be0 SL |
558 | fn first<A, B>((a, _): (A, B)) -> A { |
559 | a | |
560 | } | |
9346a6ac AL |
561 | let first: fn((T, ())) -> T = first; // coerce to fn pointer |
562 | ||
563 | IntoIter { iter: self.map.into_iter().map(first) } | |
85aaf69f SL |
564 | } |
565 | } | |
566 | ||
567 | #[stable(feature = "rust1", since = "1.0.0")] | |
568 | impl<'a, T> IntoIterator for &'a BTreeSet<T> { | |
569 | type Item = &'a T; | |
570 | type IntoIter = Iter<'a, T>; | |
571 | ||
572 | fn into_iter(self) -> Iter<'a, T> { | |
573 | self.iter() | |
574 | } | |
575 | } | |
576 | ||
577 | #[stable(feature = "rust1", since = "1.0.0")] | |
1a4d82fc JJ |
578 | impl<T: Ord> Extend<T> for BTreeSet<T> { |
579 | #[inline] | |
92a42be0 | 580 | fn extend<Iter: IntoIterator<Item = T>>(&mut self, iter: Iter) { |
1a4d82fc JJ |
581 | for elem in iter { |
582 | self.insert(elem); | |
583 | } | |
584 | } | |
585 | } | |
586 | ||
62682a34 SL |
587 | #[stable(feature = "extend_ref", since = "1.2.0")] |
588 | impl<'a, T: 'a + Ord + Copy> Extend<&'a T> for BTreeSet<T> { | |
92a42be0 | 589 | fn extend<I: IntoIterator<Item = &'a T>>(&mut self, iter: I) { |
62682a34 SL |
590 | self.extend(iter.into_iter().cloned()); |
591 | } | |
592 | } | |
593 | ||
85aaf69f | 594 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 595 | impl<T: Ord> Default for BTreeSet<T> { |
1a4d82fc JJ |
596 | fn default() -> BTreeSet<T> { |
597 | BTreeSet::new() | |
598 | } | |
599 | } | |
600 | ||
85aaf69f | 601 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
602 | impl<'a, 'b, T: Ord + Clone> Sub<&'b BTreeSet<T>> for &'a BTreeSet<T> { |
603 | type Output = BTreeSet<T>; | |
604 | ||
605 | /// Returns the difference of `self` and `rhs` as a new `BTreeSet<T>`. | |
606 | /// | |
607 | /// # Examples | |
608 | /// | |
609 | /// ``` | |
610 | /// use std::collections::BTreeSet; | |
611 | /// | |
85aaf69f SL |
612 | /// let a: BTreeSet<_> = vec![1, 2, 3].into_iter().collect(); |
613 | /// let b: BTreeSet<_> = vec![3, 4, 5].into_iter().collect(); | |
1a4d82fc | 614 | /// |
85aaf69f SL |
615 | /// let result = &a - &b; |
616 | /// let result_vec: Vec<_> = result.into_iter().collect(); | |
c34b1796 | 617 | /// assert_eq!(result_vec, [1, 2]); |
1a4d82fc JJ |
618 | /// ``` |
619 | fn sub(self, rhs: &BTreeSet<T>) -> BTreeSet<T> { | |
620 | self.difference(rhs).cloned().collect() | |
621 | } | |
622 | } | |
623 | ||
85aaf69f | 624 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
625 | impl<'a, 'b, T: Ord + Clone> BitXor<&'b BTreeSet<T>> for &'a BTreeSet<T> { |
626 | type Output = BTreeSet<T>; | |
627 | ||
628 | /// Returns the symmetric difference of `self` and `rhs` as a new `BTreeSet<T>`. | |
629 | /// | |
630 | /// # Examples | |
631 | /// | |
632 | /// ``` | |
633 | /// use std::collections::BTreeSet; | |
634 | /// | |
85aaf69f SL |
635 | /// let a: BTreeSet<_> = vec![1, 2, 3].into_iter().collect(); |
636 | /// let b: BTreeSet<_> = vec![2, 3, 4].into_iter().collect(); | |
1a4d82fc | 637 | /// |
85aaf69f SL |
638 | /// let result = &a ^ &b; |
639 | /// let result_vec: Vec<_> = result.into_iter().collect(); | |
c34b1796 | 640 | /// assert_eq!(result_vec, [1, 4]); |
1a4d82fc JJ |
641 | /// ``` |
642 | fn bitxor(self, rhs: &BTreeSet<T>) -> BTreeSet<T> { | |
643 | self.symmetric_difference(rhs).cloned().collect() | |
644 | } | |
645 | } | |
646 | ||
85aaf69f | 647 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
648 | impl<'a, 'b, T: Ord + Clone> BitAnd<&'b BTreeSet<T>> for &'a BTreeSet<T> { |
649 | type Output = BTreeSet<T>; | |
650 | ||
651 | /// Returns the intersection of `self` and `rhs` as a new `BTreeSet<T>`. | |
652 | /// | |
653 | /// # Examples | |
654 | /// | |
655 | /// ``` | |
656 | /// use std::collections::BTreeSet; | |
657 | /// | |
85aaf69f SL |
658 | /// let a: BTreeSet<_> = vec![1, 2, 3].into_iter().collect(); |
659 | /// let b: BTreeSet<_> = vec![2, 3, 4].into_iter().collect(); | |
1a4d82fc | 660 | /// |
85aaf69f SL |
661 | /// let result = &a & &b; |
662 | /// let result_vec: Vec<_> = result.into_iter().collect(); | |
c34b1796 | 663 | /// assert_eq!(result_vec, [2, 3]); |
1a4d82fc JJ |
664 | /// ``` |
665 | fn bitand(self, rhs: &BTreeSet<T>) -> BTreeSet<T> { | |
666 | self.intersection(rhs).cloned().collect() | |
667 | } | |
668 | } | |
669 | ||
85aaf69f | 670 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
671 | impl<'a, 'b, T: Ord + Clone> BitOr<&'b BTreeSet<T>> for &'a BTreeSet<T> { |
672 | type Output = BTreeSet<T>; | |
673 | ||
674 | /// Returns the union of `self` and `rhs` as a new `BTreeSet<T>`. | |
675 | /// | |
676 | /// # Examples | |
677 | /// | |
678 | /// ``` | |
679 | /// use std::collections::BTreeSet; | |
680 | /// | |
85aaf69f SL |
681 | /// let a: BTreeSet<_> = vec![1, 2, 3].into_iter().collect(); |
682 | /// let b: BTreeSet<_> = vec![3, 4, 5].into_iter().collect(); | |
1a4d82fc | 683 | /// |
85aaf69f SL |
684 | /// let result = &a | &b; |
685 | /// let result_vec: Vec<_> = result.into_iter().collect(); | |
c34b1796 | 686 | /// assert_eq!(result_vec, [1, 2, 3, 4, 5]); |
1a4d82fc JJ |
687 | /// ``` |
688 | fn bitor(self, rhs: &BTreeSet<T>) -> BTreeSet<T> { | |
689 | self.union(rhs).cloned().collect() | |
690 | } | |
691 | } | |
692 | ||
85aaf69f SL |
693 | #[stable(feature = "rust1", since = "1.0.0")] |
694 | impl<T: Debug> Debug for BTreeSet<T> { | |
1a4d82fc | 695 | fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
62682a34 | 696 | f.debug_set().entries(self.iter()).finish() |
1a4d82fc JJ |
697 | } |
698 | } | |
699 | ||
c34b1796 | 700 | impl<'a, T> Clone for Iter<'a, T> { |
92a42be0 SL |
701 | fn clone(&self) -> Iter<'a, T> { |
702 | Iter { iter: self.iter.clone() } | |
703 | } | |
c34b1796 | 704 | } |
85aaf69f | 705 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
706 | impl<'a, T> Iterator for Iter<'a, T> { |
707 | type Item = &'a T; | |
708 | ||
92a42be0 SL |
709 | fn next(&mut self) -> Option<&'a T> { |
710 | self.iter.next() | |
711 | } | |
712 | fn size_hint(&self) -> (usize, Option<usize>) { | |
713 | self.iter.size_hint() | |
714 | } | |
1a4d82fc | 715 | } |
85aaf69f | 716 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 717 | impl<'a, T> DoubleEndedIterator for Iter<'a, T> { |
92a42be0 SL |
718 | fn next_back(&mut self) -> Option<&'a T> { |
719 | self.iter.next_back() | |
720 | } | |
1a4d82fc | 721 | } |
85aaf69f | 722 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
723 | impl<'a, T> ExactSizeIterator for Iter<'a, T> {} |
724 | ||
725 | ||
85aaf69f | 726 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
727 | impl<T> Iterator for IntoIter<T> { |
728 | type Item = T; | |
729 | ||
92a42be0 SL |
730 | fn next(&mut self) -> Option<T> { |
731 | self.iter.next() | |
732 | } | |
733 | fn size_hint(&self) -> (usize, Option<usize>) { | |
734 | self.iter.size_hint() | |
735 | } | |
1a4d82fc | 736 | } |
85aaf69f | 737 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc | 738 | impl<T> DoubleEndedIterator for IntoIter<T> { |
92a42be0 SL |
739 | fn next_back(&mut self) -> Option<T> { |
740 | self.iter.next_back() | |
741 | } | |
1a4d82fc | 742 | } |
85aaf69f | 743 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
744 | impl<T> ExactSizeIterator for IntoIter<T> {} |
745 | ||
85aaf69f | 746 | |
c34b1796 | 747 | impl<'a, T> Clone for Range<'a, T> { |
92a42be0 SL |
748 | fn clone(&self) -> Range<'a, T> { |
749 | Range { iter: self.iter.clone() } | |
750 | } | |
c34b1796 | 751 | } |
85aaf69f SL |
752 | impl<'a, T> Iterator for Range<'a, T> { |
753 | type Item = &'a T; | |
754 | ||
92a42be0 SL |
755 | fn next(&mut self) -> Option<&'a T> { |
756 | self.iter.next() | |
757 | } | |
85aaf69f SL |
758 | } |
759 | impl<'a, T> DoubleEndedIterator for Range<'a, T> { | |
92a42be0 SL |
760 | fn next_back(&mut self) -> Option<&'a T> { |
761 | self.iter.next_back() | |
762 | } | |
85aaf69f SL |
763 | } |
764 | ||
1a4d82fc | 765 | /// Compare `x` and `y`, but return `short` if x is None and `long` if y is None |
92a42be0 | 766 | fn cmp_opt<T: Ord>(x: Option<&T>, y: Option<&T>, short: Ordering, long: Ordering) -> Ordering { |
1a4d82fc | 767 | match (x, y) { |
92a42be0 SL |
768 | (None, _) => short, |
769 | (_, None) => long, | |
1a4d82fc JJ |
770 | (Some(x1), Some(y1)) => x1.cmp(y1), |
771 | } | |
772 | } | |
773 | ||
c34b1796 AL |
774 | impl<'a, T> Clone for Difference<'a, T> { |
775 | fn clone(&self) -> Difference<'a, T> { | |
92a42be0 SL |
776 | Difference { |
777 | a: self.a.clone(), | |
778 | b: self.b.clone(), | |
779 | } | |
c34b1796 AL |
780 | } |
781 | } | |
85aaf69f | 782 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
783 | impl<'a, T: Ord> Iterator for Difference<'a, T> { |
784 | type Item = &'a T; | |
785 | ||
786 | fn next(&mut self) -> Option<&'a T> { | |
787 | loop { | |
788 | match cmp_opt(self.a.peek(), self.b.peek(), Less, Less) { | |
92a42be0 SL |
789 | Less => return self.a.next(), |
790 | Equal => { | |
791 | self.a.next(); | |
792 | self.b.next(); | |
793 | } | |
794 | Greater => { | |
795 | self.b.next(); | |
796 | } | |
1a4d82fc JJ |
797 | } |
798 | } | |
799 | } | |
800 | } | |
801 | ||
c34b1796 AL |
802 | impl<'a, T> Clone for SymmetricDifference<'a, T> { |
803 | fn clone(&self) -> SymmetricDifference<'a, T> { | |
92a42be0 SL |
804 | SymmetricDifference { |
805 | a: self.a.clone(), | |
806 | b: self.b.clone(), | |
807 | } | |
c34b1796 AL |
808 | } |
809 | } | |
85aaf69f | 810 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
811 | impl<'a, T: Ord> Iterator for SymmetricDifference<'a, T> { |
812 | type Item = &'a T; | |
813 | ||
814 | fn next(&mut self) -> Option<&'a T> { | |
815 | loop { | |
816 | match cmp_opt(self.a.peek(), self.b.peek(), Greater, Less) { | |
92a42be0 SL |
817 | Less => return self.a.next(), |
818 | Equal => { | |
819 | self.a.next(); | |
820 | self.b.next(); | |
821 | } | |
1a4d82fc JJ |
822 | Greater => return self.b.next(), |
823 | } | |
824 | } | |
825 | } | |
826 | } | |
827 | ||
c34b1796 AL |
828 | impl<'a, T> Clone for Intersection<'a, T> { |
829 | fn clone(&self) -> Intersection<'a, T> { | |
92a42be0 SL |
830 | Intersection { |
831 | a: self.a.clone(), | |
832 | b: self.b.clone(), | |
833 | } | |
c34b1796 AL |
834 | } |
835 | } | |
85aaf69f | 836 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
837 | impl<'a, T: Ord> Iterator for Intersection<'a, T> { |
838 | type Item = &'a T; | |
839 | ||
840 | fn next(&mut self) -> Option<&'a T> { | |
841 | loop { | |
842 | let o_cmp = match (self.a.peek(), self.b.peek()) { | |
92a42be0 SL |
843 | (None, _) => None, |
844 | (_, None) => None, | |
1a4d82fc JJ |
845 | (Some(a1), Some(b1)) => Some(a1.cmp(b1)), |
846 | }; | |
847 | match o_cmp { | |
92a42be0 SL |
848 | None => return None, |
849 | Some(Less) => { | |
850 | self.a.next(); | |
851 | } | |
852 | Some(Equal) => { | |
853 | self.b.next(); | |
854 | return self.a.next(); | |
855 | } | |
856 | Some(Greater) => { | |
857 | self.b.next(); | |
858 | } | |
1a4d82fc JJ |
859 | } |
860 | } | |
861 | } | |
862 | } | |
863 | ||
c34b1796 AL |
864 | impl<'a, T> Clone for Union<'a, T> { |
865 | fn clone(&self) -> Union<'a, T> { | |
92a42be0 SL |
866 | Union { |
867 | a: self.a.clone(), | |
868 | b: self.b.clone(), | |
869 | } | |
c34b1796 AL |
870 | } |
871 | } | |
85aaf69f | 872 | #[stable(feature = "rust1", since = "1.0.0")] |
1a4d82fc JJ |
873 | impl<'a, T: Ord> Iterator for Union<'a, T> { |
874 | type Item = &'a T; | |
875 | ||
876 | fn next(&mut self) -> Option<&'a T> { | |
877 | loop { | |
878 | match cmp_opt(self.a.peek(), self.b.peek(), Greater, Less) { | |
92a42be0 SL |
879 | Less => return self.a.next(), |
880 | Equal => { | |
881 | self.b.next(); | |
882 | return self.a.next(); | |
883 | } | |
1a4d82fc JJ |
884 | Greater => return self.b.next(), |
885 | } | |
886 | } | |
887 | } | |
888 | } |