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 // ignore-lexer-test FIXME #15883
13 use borrow::BorrowFrom;
15 use cmp::{Eq, Equiv, PartialEq};
16 use core::kinds::Sized;
20 use hash::{Hash, Hasher, RandomSipHasher};
21 use iter::{Iterator, IteratorExt, IteratorCloneExt, FromIterator, Map, Chain, Extend};
22 use ops::{BitOr, BitAnd, BitXor, Sub};
23 use option::Option::{Some, None, mod};
24 use result::Result::{Ok, Err};
26 use super::map::{mod, HashMap, Keys, INITIAL_CAPACITY};
28 // Future Optimization (FIXME!)
29 // =============================
31 // Iteration over zero sized values is a noop. There is no need
32 // for `bucket.val` in the case of HashSet. I suppose we would need HKT
33 // to get rid of it properly.
35 /// An implementation of a hash set using the underlying representation of a
36 /// HashMap where the value is (). As with the `HashMap` type, a `HashSet`
37 /// requires that the elements implement the `Eq` and `Hash` traits.
42 /// use std::collections::HashSet;
43 /// // Type inference lets us omit an explicit type signature (which
44 /// // would be `HashSet<&str>` in this example).
45 /// let mut books = HashSet::new();
47 /// // Add some books.
48 /// books.insert("A Dance With Dragons");
49 /// books.insert("To Kill a Mockingbird");
50 /// books.insert("The Odyssey");
51 /// books.insert("The Great Gatsby");
53 /// // Check for a specific one.
54 /// if !books.contains(&("The Winds of Winter")) {
55 /// println!("We have {} books, but The Winds of Winter ain't one.",
60 /// books.remove(&"The Odyssey");
62 /// // Iterate over everything.
63 /// for book in books.iter() {
64 /// println!("{}", *book);
68 /// The easiest way to use `HashSet` with a custom type is to derive
69 /// `Eq` and `Hash`. We must also derive `PartialEq`, this will in the
70 /// future be implied by `Eq`.
73 /// use std::collections::HashSet;
74 /// #[deriving(Hash, Eq, PartialEq, Show)]
75 /// struct Viking<'a> {
80 /// let mut vikings = HashSet::new();
82 /// vikings.insert(Viking { name: "Einar", power: 9u });
83 /// vikings.insert(Viking { name: "Einar", power: 9u });
84 /// vikings.insert(Viking { name: "Olaf", power: 4u });
85 /// vikings.insert(Viking { name: "Harald", power: 8u });
87 /// // Use derived implementation to print the vikings.
88 /// for x in vikings.iter() {
89 /// println!("{}", x);
94 pub struct HashSet<T, H = RandomSipHasher> {
95 map: HashMap<T, (), H>
98 impl<T: Hash + Eq> HashSet<T, RandomSipHasher> {
99 /// Create an empty HashSet.
104 /// use std::collections::HashSet;
105 /// let mut set: HashSet<int> = HashSet::new();
109 pub fn new() -> HashSet<T, RandomSipHasher> {
110 HashSet::with_capacity(INITIAL_CAPACITY)
113 /// Create an empty HashSet with space for at least `n` elements in
119 /// use std::collections::HashSet;
120 /// let mut set: HashSet<int> = HashSet::with_capacity(10);
124 pub fn with_capacity(capacity: uint) -> HashSet<T, RandomSipHasher> {
125 HashSet { map: HashMap::with_capacity(capacity) }
129 impl<T: Eq + Hash<S>, S, H: Hasher<S>> HashSet<T, H> {
130 /// Creates a new empty hash set which will use the given hasher to hash
133 /// The hash set is also created with the default initial capacity.
138 /// use std::collections::HashSet;
139 /// use std::hash::sip::SipHasher;
141 /// let h = SipHasher::new();
142 /// let mut set = HashSet::with_hasher(h);
146 #[unstable = "hasher stuff is unclear"]
147 pub fn with_hasher(hasher: H) -> HashSet<T, H> {
148 HashSet::with_capacity_and_hasher(INITIAL_CAPACITY, hasher)
151 /// Create an empty HashSet with space for at least `capacity`
152 /// elements in the hash table, using `hasher` to hash the keys.
154 /// Warning: `hasher` is normally randomly generated, and
155 /// is designed to allow `HashSet`s to be resistant to attacks that
156 /// cause many collisions and very poor performance. Setting it
157 /// manually using this function can expose a DoS attack vector.
162 /// use std::collections::HashSet;
163 /// use std::hash::sip::SipHasher;
165 /// let h = SipHasher::new();
166 /// let mut set = HashSet::with_capacity_and_hasher(10u, h);
170 #[unstable = "hasher stuff is unclear"]
171 pub fn with_capacity_and_hasher(capacity: uint, hasher: H) -> HashSet<T, H> {
172 HashSet { map: HashMap::with_capacity_and_hasher(capacity, hasher) }
175 /// Returns the number of elements the set can hold without reallocating.
180 /// use std::collections::HashSet;
181 /// let set: HashSet<int> = HashSet::with_capacity(100);
182 /// assert!(set.capacity() >= 100);
186 pub fn capacity(&self) -> uint {
190 /// Reserves capacity for at least `additional` more elements to be inserted
191 /// in the `HashSet`. The collection may reserve more space to avoid
192 /// frequent reallocations.
196 /// Panics if the new allocation size overflows `uint`.
201 /// use std::collections::HashSet;
202 /// let mut set: HashSet<int> = HashSet::new();
206 pub fn reserve(&mut self, additional: uint) {
207 self.map.reserve(additional)
210 /// Shrinks the capacity of the set as much as possible. It will drop
211 /// down as much as possible while maintaining the internal rules
212 /// and possibly leaving some space in accordance with the resize policy.
217 /// use std::collections::HashSet;
219 /// let mut set: HashSet<int> = HashSet::with_capacity(100);
222 /// assert!(set.capacity() >= 100);
223 /// set.shrink_to_fit();
224 /// assert!(set.capacity() >= 2);
227 pub fn shrink_to_fit(&mut self) {
228 self.map.shrink_to_fit()
231 /// Deprecated: use `contains` and `BorrowFrom`.
232 #[deprecated = "use contains and BorrowFrom"]
234 pub fn contains_equiv<Sized? Q: Hash<S> + Equiv<T>>(&self, value: &Q) -> bool {
235 self.map.contains_key_equiv(value)
238 /// An iterator visiting all elements in arbitrary order.
239 /// Iterator element type is &'a T.
244 /// use std::collections::HashSet;
245 /// let mut set = HashSet::new();
249 /// // Will print in an arbitrary order.
250 /// for x in set.iter() {
251 /// println!("{}", x);
255 pub fn iter(&self) -> Iter<T> {
256 Iter { iter: self.map.keys() }
259 /// Creates a consuming iterator, that is, one that moves each value out
260 /// of the set in arbitrary order. The set cannot be used after calling
266 /// use std::collections::HashSet;
267 /// let mut set = HashSet::new();
268 /// set.insert("a".to_string());
269 /// set.insert("b".to_string());
271 /// // Not possible to collect to a Vec<String> with a regular `.iter()`.
272 /// let v: Vec<String> = set.into_iter().collect();
274 /// // Will print in an arbitrary order.
275 /// for x in v.iter() {
276 /// println!("{}", x);
280 pub fn into_iter(self) -> IntoIter<T> {
281 fn first<A, B>((a, _): (A, B)) -> A { a }
282 let first: fn((T, ())) -> T = first;
284 IntoIter { iter: self.map.into_iter().map(first) }
287 /// Visit the values representing the difference.
292 /// use std::collections::HashSet;
293 /// let a: HashSet<int> = [1i, 2, 3].iter().map(|&x| x).collect();
294 /// let b: HashSet<int> = [4i, 2, 3, 4].iter().map(|&x| x).collect();
296 /// // Can be seen as `a - b`.
297 /// for x in a.difference(&b) {
298 /// println!("{}", x); // Print 1
301 /// let diff: HashSet<int> = a.difference(&b).map(|&x| x).collect();
302 /// assert_eq!(diff, [1i].iter().map(|&x| x).collect());
304 /// // Note that difference is not symmetric,
305 /// // and `b - a` means something else:
306 /// let diff: HashSet<int> = b.difference(&a).map(|&x| x).collect();
307 /// assert_eq!(diff, [4i].iter().map(|&x| x).collect());
310 pub fn difference<'a>(&'a self, other: &'a HashSet<T, H>) -> Difference<'a, T, H> {
317 /// Visit the values representing the symmetric difference.
322 /// use std::collections::HashSet;
323 /// let a: HashSet<int> = [1i, 2, 3].iter().map(|&x| x).collect();
324 /// let b: HashSet<int> = [4i, 2, 3, 4].iter().map(|&x| x).collect();
326 /// // Print 1, 4 in arbitrary order.
327 /// for x in a.symmetric_difference(&b) {
328 /// println!("{}", x);
331 /// let diff1: HashSet<int> = a.symmetric_difference(&b).map(|&x| x).collect();
332 /// let diff2: HashSet<int> = b.symmetric_difference(&a).map(|&x| x).collect();
334 /// assert_eq!(diff1, diff2);
335 /// assert_eq!(diff1, [1i, 4].iter().map(|&x| x).collect());
338 pub fn symmetric_difference<'a>(&'a self, other: &'a HashSet<T, H>)
339 -> SymmetricDifference<'a, T, H> {
340 SymmetricDifference { iter: self.difference(other).chain(other.difference(self)) }
343 /// Visit the values representing the intersection.
348 /// use std::collections::HashSet;
349 /// let a: HashSet<int> = [1i, 2, 3].iter().map(|&x| x).collect();
350 /// let b: HashSet<int> = [4i, 2, 3, 4].iter().map(|&x| x).collect();
352 /// // Print 2, 3 in arbitrary order.
353 /// for x in a.intersection(&b) {
354 /// println!("{}", x);
357 /// let diff: HashSet<int> = a.intersection(&b).map(|&x| x).collect();
358 /// assert_eq!(diff, [2i, 3].iter().map(|&x| x).collect());
361 pub fn intersection<'a>(&'a self, other: &'a HashSet<T, H>) -> Intersection<'a, T, H> {
368 /// Visit the values representing the union.
373 /// use std::collections::HashSet;
374 /// let a: HashSet<int> = [1i, 2, 3].iter().map(|&x| x).collect();
375 /// let b: HashSet<int> = [4i, 2, 3, 4].iter().map(|&x| x).collect();
377 /// // Print 1, 2, 3, 4 in arbitrary order.
378 /// for x in a.union(&b) {
379 /// println!("{}", x);
382 /// let diff: HashSet<int> = a.union(&b).map(|&x| x).collect();
383 /// assert_eq!(diff, [1i, 2, 3, 4].iter().map(|&x| x).collect());
386 pub fn union<'a>(&'a self, other: &'a HashSet<T, H>) -> Union<'a, T, H> {
387 Union { iter: self.iter().chain(other.difference(self)) }
390 /// Return the number of elements in the set
395 /// use std::collections::HashSet;
397 /// let mut v = HashSet::new();
398 /// assert_eq!(v.len(), 0);
400 /// assert_eq!(v.len(), 1);
403 pub fn len(&self) -> uint { self.map.len() }
405 /// Returns true if the set contains no elements
410 /// use std::collections::HashSet;
412 /// let mut v = HashSet::new();
413 /// assert!(v.is_empty());
415 /// assert!(!v.is_empty());
418 pub fn is_empty(&self) -> bool { self.map.len() == 0 }
420 /// Clears the set, returning all elements in an iterator.
422 #[unstable = "matches collection reform specification, waiting for dust to settle"]
423 pub fn drain(&mut self) -> Drain<T> {
424 fn first<A, B>((a, _): (A, B)) -> A { a }
425 let first: fn((T, ())) -> T = first; // coerce to fn pointer
427 Drain { iter: self.map.drain().map(first) }
430 /// Clears the set, removing all values.
435 /// use std::collections::HashSet;
437 /// let mut v = HashSet::new();
440 /// assert!(v.is_empty());
443 pub fn clear(&mut self) { self.map.clear() }
445 /// Returns `true` if the set contains a value.
447 /// The value may be any borrowed form of the set's value type, but
448 /// `Hash` and `Eq` on the borrowed form *must* match those for
454 /// use std::collections::HashSet;
456 /// let set: HashSet<uint> = [1, 2, 3].iter().map(|&x| x).collect();
457 /// assert_eq!(set.contains(&1), true);
458 /// assert_eq!(set.contains(&4), false);
461 pub fn contains<Sized? Q>(&self, value: &Q) -> bool
462 where Q: BorrowFrom<T> + Hash<S> + Eq
464 self.map.contains_key(value)
467 /// Returns `true` if the set has no elements in common with `other`.
468 /// This is equivalent to checking for an empty intersection.
473 /// use std::collections::HashSet;
475 /// let a: HashSet<uint> = [1, 2, 3].iter().map(|&x| x).collect();
476 /// let mut b: HashSet<uint> = HashSet::new();
478 /// assert_eq!(a.is_disjoint(&b), true);
480 /// assert_eq!(a.is_disjoint(&b), true);
482 /// assert_eq!(a.is_disjoint(&b), false);
485 pub fn is_disjoint(&self, other: &HashSet<T, H>) -> bool {
486 self.iter().all(|v| !other.contains(v))
489 /// Returns `true` if the set is a subset of another.
494 /// use std::collections::HashSet;
496 /// let sup: HashSet<uint> = [1, 2, 3].iter().map(|&x| x).collect();
497 /// let mut set: HashSet<uint> = HashSet::new();
499 /// assert_eq!(set.is_subset(&sup), true);
501 /// assert_eq!(set.is_subset(&sup), true);
503 /// assert_eq!(set.is_subset(&sup), false);
506 pub fn is_subset(&self, other: &HashSet<T, H>) -> bool {
507 self.iter().all(|v| other.contains(v))
510 /// Returns `true` if the set is a superset of another.
515 /// use std::collections::HashSet;
517 /// let sub: HashSet<uint> = [1, 2].iter().map(|&x| x).collect();
518 /// let mut set: HashSet<uint> = HashSet::new();
520 /// assert_eq!(set.is_superset(&sub), false);
524 /// assert_eq!(set.is_superset(&sub), false);
527 /// assert_eq!(set.is_superset(&sub), true);
531 pub fn is_superset(&self, other: &HashSet<T, H>) -> bool {
532 other.is_subset(self)
535 /// Adds a value to the set. Returns `true` if the value was not already
536 /// present in the set.
541 /// use std::collections::HashSet;
543 /// let mut set = HashSet::new();
545 /// assert_eq!(set.insert(2u), true);
546 /// assert_eq!(set.insert(2), false);
547 /// assert_eq!(set.len(), 1);
550 pub fn insert(&mut self, value: T) -> bool { self.map.insert(value, ()).is_none() }
552 /// Removes a value from the set. Returns `true` if the value was
553 /// present in the set.
555 /// The value may be any borrowed form of the set's value type, but
556 /// `Hash` and `Eq` on the borrowed form *must* match those for
562 /// use std::collections::HashSet;
564 /// let mut set = HashSet::new();
567 /// assert_eq!(set.remove(&2), true);
568 /// assert_eq!(set.remove(&2), false);
571 pub fn remove<Sized? Q>(&mut self, value: &Q) -> bool
572 where Q: BorrowFrom<T> + Hash<S> + Eq
574 self.map.remove(value).is_some()
579 impl<T: Eq + Hash<S>, S, H: Hasher<S>> PartialEq for HashSet<T, H> {
580 fn eq(&self, other: &HashSet<T, H>) -> bool {
581 if self.len() != other.len() { return false; }
583 self.iter().all(|key| other.contains(key))
588 impl<T: Eq + Hash<S>, S, H: Hasher<S>> Eq for HashSet<T, H> {}
591 impl<T: Eq + Hash<S> + fmt::Show, S, H: Hasher<S>> fmt::Show for HashSet<T, H> {
592 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
593 try!(write!(f, "{{"));
595 for (i, x) in self.iter().enumerate() {
596 if i != 0 { try!(write!(f, ", ")); }
597 try!(write!(f, "{}", *x));
605 impl<T: Eq + Hash<S>, S, H: Hasher<S> + Default> FromIterator<T> for HashSet<T, H> {
606 fn from_iter<I: Iterator<T>>(iter: I) -> HashSet<T, H> {
607 let lower = iter.size_hint().0;
608 let mut set = HashSet::with_capacity_and_hasher(lower, Default::default());
615 impl<T: Eq + Hash<S>, S, H: Hasher<S> + Default> Extend<T> for HashSet<T, H> {
616 fn extend<I: Iterator<T>>(&mut self, mut iter: I) {
624 impl<T: Eq + Hash<S>, S, H: Hasher<S> + Default> Default for HashSet<T, H> {
626 fn default() -> HashSet<T, H> {
627 HashSet::with_hasher(Default::default())
632 impl<'a, 'b, T: Eq + Hash<S> + Clone, S, H: Hasher<S> + Default>
633 BitOr<&'b HashSet<T, H>, HashSet<T, H>> for &'a HashSet<T, H> {
634 /// Returns the union of `self` and `rhs` as a new `HashSet<T, H>`.
639 /// use std::collections::HashSet;
641 /// let a: HashSet<int> = vec![1, 2, 3].into_iter().collect();
642 /// let b: HashSet<int> = vec![3, 4, 5].into_iter().collect();
644 /// let set: HashSet<int> = &a | &b;
647 /// let expected = [1, 2, 3, 4, 5];
648 /// for x in set.iter() {
649 /// assert!(expected.contains(x));
652 /// assert_eq!(i, expected.len());
654 fn bitor(self, rhs: &HashSet<T, H>) -> HashSet<T, H> {
655 self.union(rhs).cloned().collect()
660 impl<'a, 'b, T: Eq + Hash<S> + Clone, S, H: Hasher<S> + Default>
661 BitAnd<&'b HashSet<T, H>, HashSet<T, H>> for &'a HashSet<T, H> {
662 /// Returns the intersection of `self` and `rhs` as a new `HashSet<T, H>`.
667 /// use std::collections::HashSet;
669 /// let a: HashSet<int> = vec![1, 2, 3].into_iter().collect();
670 /// let b: HashSet<int> = vec![2, 3, 4].into_iter().collect();
672 /// let set: HashSet<int> = &a & &b;
675 /// let expected = [2, 3];
676 /// for x in set.iter() {
677 /// assert!(expected.contains(x));
680 /// assert_eq!(i, expected.len());
682 fn bitand(self, rhs: &HashSet<T, H>) -> HashSet<T, H> {
683 self.intersection(rhs).cloned().collect()
688 impl<'a, 'b, T: Eq + Hash<S> + Clone, S, H: Hasher<S> + Default>
689 BitXor<&'b HashSet<T, H>, HashSet<T, H>> for &'a HashSet<T, H> {
690 /// Returns the symmetric difference of `self` and `rhs` as a new `HashSet<T, H>`.
695 /// use std::collections::HashSet;
697 /// let a: HashSet<int> = vec![1, 2, 3].into_iter().collect();
698 /// let b: HashSet<int> = vec![3, 4, 5].into_iter().collect();
700 /// let set: HashSet<int> = &a ^ &b;
703 /// let expected = [1, 2, 4, 5];
704 /// for x in set.iter() {
705 /// assert!(expected.contains(x));
708 /// assert_eq!(i, expected.len());
710 fn bitxor(self, rhs: &HashSet<T, H>) -> HashSet<T, H> {
711 self.symmetric_difference(rhs).cloned().collect()
716 impl<'a, 'b, T: Eq + Hash<S> + Clone, S, H: Hasher<S> + Default>
717 Sub<&'b HashSet<T, H>, HashSet<T, H>> for &'a HashSet<T, H> {
718 /// Returns the difference of `self` and `rhs` as a new `HashSet<T, H>`.
723 /// use std::collections::HashSet;
725 /// let a: HashSet<int> = vec![1, 2, 3].into_iter().collect();
726 /// let b: HashSet<int> = vec![3, 4, 5].into_iter().collect();
728 /// let set: HashSet<int> = &a - &b;
731 /// let expected = [1, 2];
732 /// for x in set.iter() {
733 /// assert!(expected.contains(x));
736 /// assert_eq!(i, expected.len());
738 fn sub(self, rhs: &HashSet<T, H>) -> HashSet<T, H> {
739 self.difference(rhs).cloned().collect()
745 pub struct Iter<'a, K: 'a> {
746 iter: Keys<'a, K, ()>
749 /// HashSet move iterator
751 pub struct IntoIter<K> {
752 iter: Map<(K, ()), K, map::IntoIter<K, ()>, fn((K, ())) -> K>
755 /// HashSet drain iterator
757 pub struct Drain<'a, K: 'a> {
758 iter: Map<(K, ()), K, map::Drain<'a, K, ()>, fn((K, ())) -> K>,
761 /// Intersection iterator
763 pub struct Intersection<'a, T: 'a, H: 'a> {
764 // iterator of the first set
767 other: &'a HashSet<T, H>,
770 /// Difference iterator
772 pub struct Difference<'a, T: 'a, H: 'a> {
773 // iterator of the first set
776 other: &'a HashSet<T, H>,
779 /// Symmetric difference iterator.
781 pub struct SymmetricDifference<'a, T: 'a, H: 'a> {
782 iter: Chain<Difference<'a, T, H>, Difference<'a, T, H>>
785 /// Set union iterator.
787 pub struct Union<'a, T: 'a, H: 'a> {
788 iter: Chain<Iter<'a, T>, Difference<'a, T, H>>
792 impl<'a, K> Iterator<&'a K> for Iter<'a, K> {
793 fn next(&mut self) -> Option<&'a K> { self.iter.next() }
794 fn size_hint(&self) -> (uint, Option<uint>) { self.iter.size_hint() }
798 impl<K> Iterator<K> for IntoIter<K> {
799 fn next(&mut self) -> Option<K> { self.iter.next() }
800 fn size_hint(&self) -> (uint, Option<uint>) { self.iter.size_hint() }
804 impl<'a, K: 'a> Iterator<K> for Drain<'a, K> {
805 fn next(&mut self) -> Option<K> { self.iter.next() }
806 fn size_hint(&self) -> (uint, Option<uint>) { self.iter.size_hint() }
810 impl<'a, T, S, H> Iterator<&'a T> for Intersection<'a, T, H>
811 where T: Eq + Hash<S>, H: Hasher<S>
813 fn next(&mut self) -> Option<&'a T> {
815 match self.iter.next() {
817 Some(elt) => if self.other.contains(elt) {
824 fn size_hint(&self) -> (uint, Option<uint>) {
825 let (_, upper) = self.iter.size_hint();
831 impl<'a, T, S, H> Iterator<&'a T> for Difference<'a, T, H>
832 where T: Eq + Hash<S>, H: Hasher<S>
834 fn next(&mut self) -> Option<&'a T> {
836 match self.iter.next() {
838 Some(elt) => if !self.other.contains(elt) {
845 fn size_hint(&self) -> (uint, Option<uint>) {
846 let (_, upper) = self.iter.size_hint();
852 impl<'a, T, S, H> Iterator<&'a T> for SymmetricDifference<'a, T, H>
853 where T: Eq + Hash<S>, H: Hasher<S>
855 fn next(&mut self) -> Option<&'a T> { self.iter.next() }
856 fn size_hint(&self) -> (uint, Option<uint>) { self.iter.size_hint() }
860 impl<'a, T, S, H> Iterator<&'a T> for Union<'a, T, H>
861 where T: Eq + Hash<S>, H: Hasher<S>
863 fn next(&mut self) -> Option<&'a T> { self.iter.next() }
864 fn size_hint(&self) -> (uint, Option<uint>) { self.iter.size_hint() }
875 let mut xs = HashSet::new();
876 let mut ys = HashSet::new();
877 assert!(xs.is_disjoint(&ys));
878 assert!(ys.is_disjoint(&xs));
879 assert!(xs.insert(5i));
880 assert!(ys.insert(11i));
881 assert!(xs.is_disjoint(&ys));
882 assert!(ys.is_disjoint(&xs));
883 assert!(xs.insert(7));
884 assert!(xs.insert(19));
885 assert!(xs.insert(4));
886 assert!(ys.insert(2));
887 assert!(ys.insert(-11));
888 assert!(xs.is_disjoint(&ys));
889 assert!(ys.is_disjoint(&xs));
890 assert!(ys.insert(7));
891 assert!(!xs.is_disjoint(&ys));
892 assert!(!ys.is_disjoint(&xs));
896 fn test_subset_and_superset() {
897 let mut a = HashSet::new();
898 assert!(a.insert(0i));
899 assert!(a.insert(5));
900 assert!(a.insert(11));
901 assert!(a.insert(7));
903 let mut b = HashSet::new();
904 assert!(b.insert(0i));
905 assert!(b.insert(7));
906 assert!(b.insert(19));
907 assert!(b.insert(250));
908 assert!(b.insert(11));
909 assert!(b.insert(200));
911 assert!(!a.is_subset(&b));
912 assert!(!a.is_superset(&b));
913 assert!(!b.is_subset(&a));
914 assert!(!b.is_superset(&a));
916 assert!(b.insert(5));
918 assert!(a.is_subset(&b));
919 assert!(!a.is_superset(&b));
920 assert!(!b.is_subset(&a));
921 assert!(b.is_superset(&a));
926 let mut a = HashSet::new();
927 for i in range(0u, 32) {
928 assert!(a.insert(i));
930 let mut observed: u32 = 0;
934 assert_eq!(observed, 0xFFFF_FFFF);
938 fn test_intersection() {
939 let mut a = HashSet::new();
940 let mut b = HashSet::new();
942 assert!(a.insert(11i));
943 assert!(a.insert(1));
944 assert!(a.insert(3));
945 assert!(a.insert(77));
946 assert!(a.insert(103));
947 assert!(a.insert(5));
948 assert!(a.insert(-5));
950 assert!(b.insert(2i));
951 assert!(b.insert(11));
952 assert!(b.insert(77));
953 assert!(b.insert(-9));
954 assert!(b.insert(-42));
955 assert!(b.insert(5));
956 assert!(b.insert(3));
959 let expected = [3, 5, 11, 77];
960 for x in a.intersection(&b) {
961 assert!(expected.contains(x));
964 assert_eq!(i, expected.len());
968 fn test_difference() {
969 let mut a = HashSet::new();
970 let mut b = HashSet::new();
972 assert!(a.insert(1i));
973 assert!(a.insert(3));
974 assert!(a.insert(5));
975 assert!(a.insert(9));
976 assert!(a.insert(11));
978 assert!(b.insert(3i));
979 assert!(b.insert(9));
982 let expected = [1, 5, 11];
983 for x in a.difference(&b) {
984 assert!(expected.contains(x));
987 assert_eq!(i, expected.len());
991 fn test_symmetric_difference() {
992 let mut a = HashSet::new();
993 let mut b = HashSet::new();
995 assert!(a.insert(1i));
996 assert!(a.insert(3));
997 assert!(a.insert(5));
998 assert!(a.insert(9));
999 assert!(a.insert(11));
1001 assert!(b.insert(-2i));
1002 assert!(b.insert(3));
1003 assert!(b.insert(9));
1004 assert!(b.insert(14));
1005 assert!(b.insert(22));
1008 let expected = [-2, 1, 5, 11, 14, 22];
1009 for x in a.symmetric_difference(&b) {
1010 assert!(expected.contains(x));
1013 assert_eq!(i, expected.len());
1018 let mut a = HashSet::new();
1019 let mut b = HashSet::new();
1021 assert!(a.insert(1i));
1022 assert!(a.insert(3));
1023 assert!(a.insert(5));
1024 assert!(a.insert(9));
1025 assert!(a.insert(11));
1026 assert!(a.insert(16));
1027 assert!(a.insert(19));
1028 assert!(a.insert(24));
1030 assert!(b.insert(-2i));
1031 assert!(b.insert(1));
1032 assert!(b.insert(5));
1033 assert!(b.insert(9));
1034 assert!(b.insert(13));
1035 assert!(b.insert(19));
1038 let expected = [-2, 1, 3, 5, 9, 11, 13, 16, 19, 24];
1039 for x in a.union(&b) {
1040 assert!(expected.contains(x));
1043 assert_eq!(i, expected.len());
1047 fn test_from_iter() {
1048 let xs = [1i, 2, 3, 4, 5, 6, 7, 8, 9];
1050 let set: HashSet<int> = xs.iter().map(|&x| x).collect();
1052 for x in xs.iter() {
1053 assert!(set.contains(x));
1058 fn test_move_iter() {
1060 let mut hs = HashSet::new();
1068 let v = hs.into_iter().collect::<Vec<char>>();
1069 assert!(['a', 'b'] == v || ['b', 'a'] == v);
1074 // These constants once happened to expose a bug in insert().
1075 // I'm keeping them around to prevent a regression.
1076 let mut s1 = HashSet::new();
1082 let mut s2 = HashSet::new();
1096 let mut set: HashSet<int> = HashSet::new();
1097 let empty: HashSet<int> = HashSet::new();
1102 let set_str = format!("{}", set);
1104 assert!(set_str == "{1, 2}" || set_str == "{2, 1}");
1105 assert_eq!(format!("{}", empty), "{}");
1109 fn test_trivial_drain() {
1110 let mut s = HashSet::<int>::new();
1111 for _ in s.drain() {}
1112 assert!(s.is_empty());
1115 let mut s = HashSet::<int>::new();
1117 assert!(s.is_empty());
1122 let mut s: HashSet<int> = range(1, 100).collect();
1124 // try this a bunch of times to make sure we don't screw up internal state.
1125 for _ in range(0i, 20) {
1126 assert_eq!(s.len(), 99);
1130 let mut d = s.drain();
1131 for (i, x) in d.by_ref().take(50).enumerate() {
1135 assert_eq!(last_i, 49);
1138 for _ in s.iter() { panic!("s should be empty!"); }
1140 // reset to try again.
1141 s.extend(range(1, 100));