1 // Copyright 2012-2014 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 // FIXME(Gankro): Bitv and BitvSet are very tightly coupled. Ideally (for
12 // maintenance), they should be in separate files/modules, with BitvSet only
13 // using Bitv's public API. This will be hard for performance though, because
14 // `Bitv` will not want to leak its internal representation while its internal
15 // representation as `u32`s must be assumed for best performance.
17 // FIXME(tbu-): `Bitv`'s methods shouldn't be `union`, `intersection`, but
18 // rather `or` and `and`.
20 // (1) Be careful, most things can overflow here because the amount of bits in
21 // memory can overflow `uint`.
22 // (2) Make sure that the underlying vector has no excess length:
23 // E. g. `nbits == 16`, `storage.len() == 2` would be excess length,
24 // because the last word isn't used at all. This is important because some
25 // methods rely on it (for *CORRECTNESS*).
26 // (3) Make sure that the unused bits in the last word are zeroed out, again
27 // other methods rely on it for *CORRECTNESS*.
28 // (4) `BitvSet` is tightly coupled with `Bitv`, so any changes you make in
29 // `Bitv` will need to be reflected in `BitvSet`.
31 //! Collections implemented with bit vectors.
35 //! This is a simple example of the [Sieve of Eratosthenes][sieve]
36 //! which calculates prime numbers up to a given limit.
38 //! [sieve]: http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes
41 //! use std::collections::{BitvSet, Bitv};
42 //! use std::num::Float;
45 //! let max_prime = 10000;
47 //! // Store the primes as a BitvSet
49 //! // Assume all numbers are prime to begin, and then we
50 //! // cross off non-primes progressively
51 //! let mut bv = Bitv::from_elem(max_prime, true);
53 //! // Neither 0 nor 1 are prime
57 //! for i in iter::range_inclusive(2, (max_prime as f64).sqrt() as uint) {
58 //! // if i is a prime
60 //! // Mark all multiples of i as non-prime (any multiples below i * i
61 //! // will have been marked as non-prime previously)
62 //! for j in iter::range_step(i * i, max_prime, i) { bv.set(j, false) }
65 //! BitvSet::from_bitv(bv)
68 //! // Simple primality tests below our max bound
69 //! let print_primes = 20;
70 //! print!("The primes below {} are: ", print_primes);
71 //! for x in range(0, print_primes) {
72 //! if primes.contains(&x) {
78 //! // We can manipulate the internal Bitv
79 //! let num_primes = primes.get_ref().iter().filter(|x| *x).count();
80 //! println!("There are {} primes below {}", num_primes, max_prime);
85 use core::cmp::Ordering;
87 use core::default::Default;
90 use core::iter::RandomAccessIterator;
91 use core::iter::{Chain, Enumerate, Repeat, Skip, Take, repeat, Cloned};
92 use core::iter::{self, FromIterator};
96 use core::{u8, u32, uint};
97 use bitv_set; //so meta
101 type Blocks<'a> = Cloned<slice::Iter<'a, u32>>;
102 type MutBlocks<'a> = slice::IterMut<'a, u32>;
103 type MatchWords<'a> = Chain<Enumerate<Blocks<'a>>, Skip<Take<Enumerate<Repeat<u32>>>>>;
105 fn reverse_bits(byte: u8) -> u8 {
107 for i in range(0, u8::BITS) {
108 result |= ((byte >> i) & 1) << (u8::BITS - 1 - i);
113 // Take two BitV's, and return iterators of their words, where the shorter one
114 // has been padded with 0's
115 fn match_words <'a,'b>(a: &'a Bitv, b: &'b Bitv) -> (MatchWords<'a>, MatchWords<'b>) {
116 let a_len = a.storage.len();
117 let b_len = b.storage.len();
119 // have to uselessly pretend to pad the longer one for type matching
121 (a.blocks().enumerate().chain(iter::repeat(0u32).enumerate().take(b_len).skip(a_len)),
122 b.blocks().enumerate().chain(iter::repeat(0u32).enumerate().take(0).skip(0)))
124 (a.blocks().enumerate().chain(iter::repeat(0u32).enumerate().take(0).skip(0)),
125 b.blocks().enumerate().chain(iter::repeat(0u32).enumerate().take(a_len).skip(b_len)))
129 static TRUE: bool = true;
130 static FALSE: bool = false;
132 /// The bitvector type.
137 /// use std::collections::Bitv;
139 /// let mut bv = Bitv::from_elem(10, false);
141 /// // insert all primes less than 10
146 /// println!("{:?}", bv);
147 /// println!("total bits set to true: {}", bv.iter().filter(|x| *x).count());
149 /// // flip all values in bitvector, producing non-primes less than 10
151 /// println!("{:?}", bv);
152 /// println!("total bits set to true: {}", bv.iter().filter(|x| *x).count());
154 /// // reset bitvector to empty
156 /// println!("{:?}", bv);
157 /// println!("total bits set to true: {}", bv.iter().filter(|x| *x).count());
159 #[unstable = "RFC 509"]
161 /// Internal representation of the bit vector
163 /// The number of valid bits in the internal representation
167 // FIXME(Gankro): NopeNopeNopeNopeNope (wait for IndexGet to be a thing)
168 impl Index<uint> for Bitv {
172 fn index(&self, i: &uint) -> &bool {
173 if self.get(*i).expect("index out of bounds") {
181 /// Computes how many blocks are needed to store that many bits
182 fn blocks_for_bits(bits: uint) -> uint {
183 // If we want 17 bits, dividing by 32 will produce 0. So we add 1 to make sure we
184 // reserve enough. But if we want exactly a multiple of 32, this will actually allocate
185 // one too many. So we need to check if that's the case. We can do that by computing if
186 // bitwise AND by `32 - 1` is 0. But LLVM should be able to optimize the semantically
187 // superior modulo operator on a power of two to this.
189 // Note that we can technically avoid this branch with the expression
190 // `(nbits + u32::BITS - 1) / 32::BITS`, but if nbits is almost uint::MAX this will overflow.
191 if bits % u32::BITS == 0 {
198 /// Computes the bitmask for the final word of the vector
199 fn mask_for_bits(bits: uint) -> u32 {
200 // Note especially that a perfect multiple of u32::BITS should mask all 1s.
201 !0u32 >> (u32::BITS - bits % u32::BITS) % u32::BITS
205 /// Applies the given operation to the blocks of self and other, and sets
206 /// self to be the result. This relies on the caller not to corrupt the
209 fn process<F>(&mut self, other: &Bitv, mut op: F) -> bool where F: FnMut(u32, u32) -> u32 {
210 assert_eq!(self.len(), other.len());
211 // This could theoretically be a `debug_assert!`.
212 assert_eq!(self.storage.len(), other.storage.len());
213 let mut changed = false;
214 for (a, b) in self.blocks_mut().zip(other.blocks()) {
224 /// Iterator over mutable refs to the underlying blocks of data.
225 fn blocks_mut(&mut self) -> MutBlocks {
227 self.storage.iter_mut()
230 /// Iterator over the underlying blocks of data
231 fn blocks(&self) -> Blocks {
233 self.storage.iter().cloned()
236 /// An operation might screw up the unused bits in the last block of the
237 /// `Bitv`. As per (3), it's assumed to be all 0s. This method fixes it up.
238 fn fix_last_block(&mut self) {
239 let extra_bits = self.len() % u32::BITS;
241 let mask = (1 << extra_bits) - 1;
242 let storage_len = self.storage.len();
243 self.storage[storage_len - 1] &= mask;
247 /// Creates an empty `Bitv`.
252 /// use std::collections::Bitv;
253 /// let mut bv = Bitv::new();
256 pub fn new() -> Bitv {
257 Bitv { storage: Vec::new(), nbits: 0 }
260 /// Creates a `Bitv` that holds `nbits` elements, setting each element
266 /// use std::collections::Bitv;
268 /// let mut bv = Bitv::from_elem(10u, false);
269 /// assert_eq!(bv.len(), 10u);
270 /// for x in bv.iter() {
271 /// assert_eq!(x, false);
274 pub fn from_elem(nbits: uint, bit: bool) -> Bitv {
275 let nblocks = blocks_for_bits(nbits);
276 let mut bitv = Bitv {
277 storage: repeat(if bit { !0u32 } else { 0u32 }).take(nblocks).collect(),
280 bitv.fix_last_block();
284 /// Constructs a new, empty `Bitv` with the specified capacity.
286 /// The bitvector will be able to hold at least `capacity` bits without
287 /// reallocating. If `capacity` is 0, it will not allocate.
289 /// It is important to note that this function does not specify the
290 /// *length* of the returned bitvector, but only the *capacity*.
292 pub fn with_capacity(nbits: uint) -> Bitv {
294 storage: Vec::with_capacity(blocks_for_bits(nbits)),
299 /// Transforms a byte-vector into a `Bitv`. Each byte becomes eight bits,
300 /// with the most significant bits of each byte coming first. Each
301 /// bit becomes `true` if equal to 1 or `false` if equal to 0.
306 /// use std::collections::Bitv;
308 /// let bv = Bitv::from_bytes(&[0b10100000, 0b00010010]);
309 /// assert!(bv.eq_vec(&[true, false, true, false,
310 /// false, false, false, false,
311 /// false, false, false, true,
312 /// false, false, true, false]));
314 pub fn from_bytes(bytes: &[u8]) -> Bitv {
315 let len = bytes.len().checked_mul(u8::BITS).expect("capacity overflow");
316 let mut bitv = Bitv::with_capacity(len);
317 let complete_words = bytes.len() / 4;
318 let extra_bytes = bytes.len() % 4;
322 for i in range(0, complete_words) {
324 ((reverse_bits(bytes[i * 4 + 0]) as u32) << 0) |
325 ((reverse_bits(bytes[i * 4 + 1]) as u32) << 8) |
326 ((reverse_bits(bytes[i * 4 + 2]) as u32) << 16) |
327 ((reverse_bits(bytes[i * 4 + 3]) as u32) << 24)
332 let mut last_word = 0u32;
333 for (i, &byte) in bytes[complete_words*4..].iter().enumerate() {
334 last_word |= (reverse_bits(byte) as u32) << (i * 8);
336 bitv.storage.push(last_word);
342 /// Creates a `Bitv` of the specified length where the value at each index
348 /// use std::collections::Bitv;
350 /// let bv = Bitv::from_fn(5, |i| { i % 2 == 0 });
351 /// assert!(bv.eq_vec(&[true, false, true, false, true]));
353 pub fn from_fn<F>(len: uint, mut f: F) -> Bitv where F: FnMut(uint) -> bool {
354 let mut bitv = Bitv::from_elem(len, false);
355 for i in range(0u, len) {
361 /// Retrieves the value at index `i`, or `None` if the index is out of bounds.
366 /// use std::collections::Bitv;
368 /// let bv = Bitv::from_bytes(&[0b01100000]);
369 /// assert_eq!(bv.get(0), Some(false));
370 /// assert_eq!(bv.get(1), Some(true));
371 /// assert_eq!(bv.get(100), None);
373 /// // Can also use array indexing
374 /// assert_eq!(bv[1], true);
378 pub fn get(&self, i: uint) -> Option<bool> {
382 let w = i / u32::BITS;
383 let b = i % u32::BITS;
384 self.storage.get(w).map(|&block|
385 (block & (1 << b)) != 0
389 /// Sets the value of a bit at an index `i`.
393 /// Panics if `i` is out of bounds.
398 /// use std::collections::Bitv;
400 /// let mut bv = Bitv::from_elem(5, false);
402 /// assert_eq!(bv[3], true);
405 #[unstable = "panic semantics are likely to change in the future"]
406 pub fn set(&mut self, i: uint, x: bool) {
407 assert!(i < self.nbits);
408 let w = i / u32::BITS;
409 let b = i % u32::BITS;
411 let val = if x { self.storage[w] | flag }
412 else { self.storage[w] & !flag };
413 self.storage[w] = val;
416 /// Sets all bits to 1.
421 /// use std::collections::Bitv;
423 /// let before = 0b01100000;
424 /// let after = 0b11111111;
426 /// let mut bv = Bitv::from_bytes(&[before]);
428 /// assert_eq!(bv, Bitv::from_bytes(&[after]));
431 pub fn set_all(&mut self) {
432 for w in self.storage.iter_mut() { *w = !0u32; }
433 self.fix_last_block();
441 /// use std::collections::Bitv;
443 /// let before = 0b01100000;
444 /// let after = 0b10011111;
446 /// let mut bv = Bitv::from_bytes(&[before]);
448 /// assert_eq!(bv, Bitv::from_bytes(&[after]));
451 pub fn negate(&mut self) {
452 for w in self.storage.iter_mut() { *w = !*w; }
453 self.fix_last_block();
456 /// Calculates the union of two bitvectors. This acts like the bitwise `or`
459 /// Sets `self` to the union of `self` and `other`. Both bitvectors must be
460 /// the same length. Returns `true` if `self` changed.
464 /// Panics if the bitvectors are of different lengths.
469 /// use std::collections::Bitv;
471 /// let a = 0b01100100;
472 /// let b = 0b01011010;
473 /// let res = 0b01111110;
475 /// let mut a = Bitv::from_bytes(&[a]);
476 /// let b = Bitv::from_bytes(&[b]);
478 /// assert!(a.union(&b));
479 /// assert_eq!(a, Bitv::from_bytes(&[res]));
482 pub fn union(&mut self, other: &Bitv) -> bool {
483 self.process(other, |w1, w2| w1 | w2)
486 /// Calculates the intersection of two bitvectors. This acts like the
487 /// bitwise `and` function.
489 /// Sets `self` to the intersection of `self` and `other`. Both bitvectors
490 /// must be the same length. Returns `true` if `self` changed.
494 /// Panics if the bitvectors are of different lengths.
499 /// use std::collections::Bitv;
501 /// let a = 0b01100100;
502 /// let b = 0b01011010;
503 /// let res = 0b01000000;
505 /// let mut a = Bitv::from_bytes(&[a]);
506 /// let b = Bitv::from_bytes(&[b]);
508 /// assert!(a.intersect(&b));
509 /// assert_eq!(a, Bitv::from_bytes(&[res]));
512 pub fn intersect(&mut self, other: &Bitv) -> bool {
513 self.process(other, |w1, w2| w1 & w2)
516 /// Calculates the difference between two bitvectors.
518 /// Sets each element of `self` to the value of that element minus the
519 /// element of `other` at the same index. Both bitvectors must be the same
520 /// length. Returns `true` if `self` changed.
524 /// Panics if the bitvectors are of different length.
529 /// use std::collections::Bitv;
531 /// let a = 0b01100100;
532 /// let b = 0b01011010;
533 /// let a_b = 0b00100100; // a - b
534 /// let b_a = 0b00011010; // b - a
536 /// let mut bva = Bitv::from_bytes(&[a]);
537 /// let bvb = Bitv::from_bytes(&[b]);
539 /// assert!(bva.difference(&bvb));
540 /// assert_eq!(bva, Bitv::from_bytes(&[a_b]));
542 /// let bva = Bitv::from_bytes(&[a]);
543 /// let mut bvb = Bitv::from_bytes(&[b]);
545 /// assert!(bvb.difference(&bva));
546 /// assert_eq!(bvb, Bitv::from_bytes(&[b_a]));
549 pub fn difference(&mut self, other: &Bitv) -> bool {
550 self.process(other, |w1, w2| w1 & !w2)
553 /// Returns `true` if all bits are 1.
558 /// use std::collections::Bitv;
560 /// let mut bv = Bitv::from_elem(5, true);
561 /// assert_eq!(bv.all(), true);
563 /// bv.set(1, false);
564 /// assert_eq!(bv.all(), false);
566 pub fn all(&self) -> bool {
567 let mut last_word = !0u32;
568 // Check that every block but the last is all-ones...
569 self.blocks().all(|elem| {
573 // and then check the last one has enough ones
574 }) && (last_word == mask_for_bits(self.nbits))
577 /// Returns an iterator over the elements of the vector in order.
582 /// use std::collections::Bitv;
584 /// let bv = Bitv::from_bytes(&[0b01110100, 0b10010010]);
585 /// assert_eq!(bv.iter().filter(|x| *x).count(), 7);
589 pub fn iter(&self) -> Iter {
590 Iter { bitv: self, next_idx: 0, end_idx: self.nbits }
593 /// Returns `true` if all bits are 0.
598 /// use std::collections::Bitv;
600 /// let mut bv = Bitv::from_elem(10, false);
601 /// assert_eq!(bv.none(), true);
604 /// assert_eq!(bv.none(), false);
606 pub fn none(&self) -> bool {
607 self.blocks().all(|w| w == 0)
610 /// Returns `true` if any bit is 1.
615 /// use std::collections::Bitv;
617 /// let mut bv = Bitv::from_elem(10, false);
618 /// assert_eq!(bv.any(), false);
621 /// assert_eq!(bv.any(), true);
624 pub fn any(&self) -> bool {
628 /// Organises the bits into bytes, such that the first bit in the
629 /// `Bitv` becomes the high-order bit of the first byte. If the
630 /// size of the `Bitv` is not a multiple of eight then trailing bits
631 /// will be filled-in with `false`.
636 /// use std::collections::Bitv;
638 /// let mut bv = Bitv::from_elem(3, true);
639 /// bv.set(1, false);
641 /// assert_eq!(bv.to_bytes(), vec!(0b10100000));
643 /// let mut bv = Bitv::from_elem(9, false);
647 /// assert_eq!(bv.to_bytes(), vec!(0b00100000, 0b10000000));
649 pub fn to_bytes(&self) -> Vec<u8> {
650 fn bit(bitv: &Bitv, byte: uint, bit: uint) -> u8 {
651 let offset = byte * 8 + bit;
652 if offset >= bitv.nbits {
655 (bitv[offset] as u8) << (7 - bit)
659 let len = self.nbits/8 +
660 if self.nbits % 8 == 0 { 0 } else { 1 };
661 range(0, len).map(|i|
673 /// Compares a `Bitv` to a slice of `bool`s.
674 /// Both the `Bitv` and slice must have the same length.
678 /// Panics if the `Bitv` and slice are of different length.
683 /// use std::collections::Bitv;
685 /// let bv = Bitv::from_bytes(&[0b10100000]);
687 /// assert!(bv.eq_vec(&[true, false, true, false,
688 /// false, false, false, false]));
690 pub fn eq_vec(&self, v: &[bool]) -> bool {
691 assert_eq!(self.nbits, v.len());
692 iter::order::eq(self.iter(), v.iter().cloned())
695 /// Shortens a `Bitv`, dropping excess elements.
697 /// If `len` is greater than the vector's current length, this has no
703 /// use std::collections::Bitv;
705 /// let mut bv = Bitv::from_bytes(&[0b01001011]);
707 /// assert!(bv.eq_vec(&[false, true]));
710 pub fn truncate(&mut self, len: uint) {
711 if len < self.len() {
714 self.storage.truncate(blocks_for_bits(len));
715 self.fix_last_block();
719 /// Reserves capacity for at least `additional` more bits to be inserted in the given
720 /// `Bitv`. The collection may reserve more space to avoid frequent reallocations.
724 /// Panics if the new capacity overflows `uint`.
729 /// use std::collections::Bitv;
731 /// let mut bv = Bitv::from_elem(3, false);
733 /// assert_eq!(bv.len(), 3);
734 /// assert!(bv.capacity() >= 13);
737 pub fn reserve(&mut self, additional: uint) {
738 let desired_cap = self.len().checked_add(additional).expect("capacity overflow");
739 let storage_len = self.storage.len();
740 if desired_cap > self.capacity() {
741 self.storage.reserve(blocks_for_bits(desired_cap) - storage_len);
745 /// Reserves the minimum capacity for exactly `additional` more bits to be inserted in the
746 /// given `Bitv`. Does nothing if the capacity is already sufficient.
748 /// Note that the allocator may give the collection more space than it requests. Therefore
749 /// capacity can not be relied upon to be precisely minimal. Prefer `reserve` if future
750 /// insertions are expected.
754 /// Panics if the new capacity overflows `uint`.
759 /// use std::collections::Bitv;
761 /// let mut bv = Bitv::from_elem(3, false);
763 /// assert_eq!(bv.len(), 3);
764 /// assert!(bv.capacity() >= 13);
767 pub fn reserve_exact(&mut self, additional: uint) {
768 let desired_cap = self.len().checked_add(additional).expect("capacity overflow");
769 let storage_len = self.storage.len();
770 if desired_cap > self.capacity() {
771 self.storage.reserve_exact(blocks_for_bits(desired_cap) - storage_len);
775 /// Returns the capacity in bits for this bit vector. Inserting any
776 /// element less than this amount will not trigger a resizing.
781 /// use std::collections::Bitv;
783 /// let mut bv = Bitv::new();
785 /// assert!(bv.capacity() >= 10);
789 pub fn capacity(&self) -> uint {
790 self.storage.capacity().checked_mul(u32::BITS).unwrap_or(uint::MAX)
793 /// Grows the `Bitv` in-place, adding `n` copies of `value` to the `Bitv`.
797 /// Panics if the new len overflows a `uint`.
802 /// use std::collections::Bitv;
804 /// let mut bv = Bitv::from_bytes(&[0b01001011]);
805 /// bv.grow(2, true);
806 /// assert_eq!(bv.len(), 10);
807 /// assert_eq!(bv.to_bytes(), vec!(0b01001011, 0b11000000));
809 pub fn grow(&mut self, n: uint, value: bool) {
810 // Note: we just bulk set all the bits in the last word in this fn in multiple places
811 // which is technically wrong if not all of these bits are to be used. However, at the end
812 // of this fn we call `fix_last_block` at the end of this fn, which should fix this.
814 let new_nbits = self.nbits.checked_add(n).expect("capacity overflow");
815 let new_nblocks = blocks_for_bits(new_nbits);
816 let full_value = if value { !0 } else { 0 };
818 // Correct the old tail word, setting or clearing formerly unused bits
819 let old_last_word = blocks_for_bits(self.nbits) - 1;
820 if self.nbits % u32::BITS > 0 {
821 let mask = mask_for_bits(self.nbits);
823 self.storage[old_last_word] |= !mask;
825 // Extra bits are already zero by invariant.
829 // Fill in words after the old tail word
830 let stop_idx = cmp::min(self.storage.len(), new_nblocks);
831 for idx in range(old_last_word + 1, stop_idx) {
832 self.storage[idx] = full_value;
835 // Allocate new words, if needed
836 if new_nblocks > self.storage.len() {
837 let to_add = new_nblocks - self.storage.len();
838 self.storage.extend(repeat(full_value).take(to_add));
841 // Adjust internal bit count
842 self.nbits = new_nbits;
844 self.fix_last_block();
847 /// Removes the last bit from the Bitv, and returns it. Returns None if the Bitv is empty.
852 /// use std::collections::Bitv;
854 /// let mut bv = Bitv::from_bytes(&[0b01001001]);
855 /// assert_eq!(bv.pop(), Some(true));
856 /// assert_eq!(bv.pop(), Some(false));
857 /// assert_eq!(bv.len(), 6);
860 pub fn pop(&mut self) -> Option<bool> {
864 let i = self.nbits - 1;
869 if self.nbits % u32::BITS == 0 {
877 /// Pushes a `bool` onto the end.
882 /// use std::collections::Bitv;
884 /// let mut bv = Bitv::new();
887 /// assert!(bv.eq_vec(&[true, false]));
890 pub fn push(&mut self, elem: bool) {
891 if self.nbits % u32::BITS == 0 {
892 self.storage.push(0);
894 let insert_pos = self.nbits;
895 self.nbits = self.nbits.checked_add(1).expect("Capacity overflow");
896 self.set(insert_pos, elem);
899 /// Return the total number of bits in this vector
902 pub fn len(&self) -> uint { self.nbits }
904 /// Returns true if there are no bits in this vector
907 pub fn is_empty(&self) -> bool { self.len() == 0 }
909 /// Clears all bits in this vector.
912 pub fn clear(&mut self) {
913 for w in self.storage.iter_mut() { *w = 0u32; }
918 impl Default for Bitv {
920 fn default() -> Bitv { Bitv::new() }
924 impl FromIterator<bool> for Bitv {
925 fn from_iter<I:Iterator<Item=bool>>(iterator: I) -> Bitv {
926 let mut ret = Bitv::new();
927 ret.extend(iterator);
933 impl Extend<bool> for Bitv {
935 fn extend<I: Iterator<Item=bool>>(&mut self, mut iterator: I) {
936 let (min, _) = iterator.size_hint();
938 for element in iterator {
945 impl Clone for Bitv {
947 fn clone(&self) -> Bitv {
948 Bitv { storage: self.storage.clone(), nbits: self.nbits }
952 fn clone_from(&mut self, source: &Bitv) {
953 self.nbits = source.nbits;
954 self.storage.clone_from(&source.storage);
959 impl PartialOrd for Bitv {
961 fn partial_cmp(&self, other: &Bitv) -> Option<Ordering> {
962 iter::order::partial_cmp(self.iter(), other.iter())
969 fn cmp(&self, other: &Bitv) -> Ordering {
970 iter::order::cmp(self.iter(), other.iter())
975 impl fmt::Show for Bitv {
976 fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
977 for bit in self.iter() {
978 try!(write!(fmt, "{}", if bit { 1u32 } else { 0u32 }));
985 impl<S: hash::Writer + hash::Hasher> hash::Hash<S> for Bitv {
986 fn hash(&self, state: &mut S) {
987 self.nbits.hash(state);
988 for elem in self.blocks() {
995 impl cmp::PartialEq for Bitv {
997 fn eq(&self, other: &Bitv) -> bool {
998 if self.nbits != other.nbits {
1001 self.blocks().zip(other.blocks()).all(|(w1, w2)| w1 == w2)
1006 impl cmp::Eq for Bitv {}
1008 /// An iterator for `Bitv`.
1011 pub struct Iter<'a> {
1018 impl<'a> Iterator for Iter<'a> {
1022 fn next(&mut self) -> Option<bool> {
1023 if self.next_idx != self.end_idx {
1024 let idx = self.next_idx;
1026 Some(self.bitv[idx])
1032 fn size_hint(&self) -> (uint, Option<uint>) {
1033 let rem = self.end_idx - self.next_idx;
1039 impl<'a> DoubleEndedIterator for Iter<'a> {
1041 fn next_back(&mut self) -> Option<bool> {
1042 if self.next_idx != self.end_idx {
1044 Some(self.bitv[self.end_idx])
1052 impl<'a> ExactSizeIterator for Iter<'a> {}
1055 impl<'a> RandomAccessIterator for Iter<'a> {
1057 fn indexable(&self) -> uint {
1058 self.end_idx - self.next_idx
1062 fn idx(&mut self, index: uint) -> Option<bool> {
1063 if index >= self.indexable() {
1066 Some(self.bitv[index])
1071 /// An implementation of a set using a bit vector as an underlying
1072 /// representation for holding unsigned numerical elements.
1074 /// It should also be noted that the amount of storage necessary for holding a
1075 /// set of objects is proportional to the maximum of the objects when viewed
1081 /// use std::collections::{BitvSet, Bitv};
1083 /// // It's a regular set
1084 /// let mut s = BitvSet::new();
1091 /// if !s.contains(&7) {
1092 /// println!("There is no 7");
1095 /// // Can initialize from a `Bitv`
1096 /// let other = BitvSet::from_bitv(Bitv::from_bytes(&[0b11010000]));
1098 /// s.union_with(&other);
1100 /// // Print 0, 1, 3 in some order
1101 /// for x in s.iter() {
1102 /// println!("{}", x);
1105 /// // Can convert back to a `Bitv`
1106 /// let bv: Bitv = s.into_bitv();
1110 #[unstable = "RFC 509"]
1111 pub struct BitvSet {
1116 impl Default for BitvSet {
1118 fn default() -> BitvSet { BitvSet::new() }
1122 impl FromIterator<uint> for BitvSet {
1123 fn from_iter<I:Iterator<Item=uint>>(iterator: I) -> BitvSet {
1124 let mut ret = BitvSet::new();
1125 ret.extend(iterator);
1131 impl Extend<uint> for BitvSet {
1133 fn extend<I: Iterator<Item=uint>>(&mut self, mut iterator: I) {
1141 impl PartialOrd for BitvSet {
1143 fn partial_cmp(&self, other: &BitvSet) -> Option<Ordering> {
1144 let (a_iter, b_iter) = match_words(self.get_ref(), other.get_ref());
1145 iter::order::partial_cmp(a_iter, b_iter)
1150 impl Ord for BitvSet {
1152 fn cmp(&self, other: &BitvSet) -> Ordering {
1153 let (a_iter, b_iter) = match_words(self.get_ref(), other.get_ref());
1154 iter::order::cmp(a_iter, b_iter)
1159 impl cmp::PartialEq for BitvSet {
1161 fn eq(&self, other: &BitvSet) -> bool {
1162 let (a_iter, b_iter) = match_words(self.get_ref(), other.get_ref());
1163 iter::order::eq(a_iter, b_iter)
1168 impl cmp::Eq for BitvSet {}
1171 /// Creates a new empty `BitvSet`.
1176 /// use std::collections::BitvSet;
1178 /// let mut s = BitvSet::new();
1182 pub fn new() -> BitvSet {
1183 BitvSet { bitv: Bitv::new() }
1186 /// Creates a new `BitvSet` with initially no contents, able to
1187 /// hold `nbits` elements without resizing.
1192 /// use std::collections::BitvSet;
1194 /// let mut s = BitvSet::with_capacity(100);
1195 /// assert!(s.capacity() >= 100);
1199 pub fn with_capacity(nbits: uint) -> BitvSet {
1200 let bitv = Bitv::from_elem(nbits, false);
1201 BitvSet::from_bitv(bitv)
1204 /// Creates a new `BitvSet` from the given bit vector.
1209 /// use std::collections::{Bitv, BitvSet};
1211 /// let bv = Bitv::from_bytes(&[0b01100000]);
1212 /// let s = BitvSet::from_bitv(bv);
1214 /// // Print 1, 2 in arbitrary order
1215 /// for x in s.iter() {
1216 /// println!("{}", x);
1220 pub fn from_bitv(bitv: Bitv) -> BitvSet {
1221 BitvSet { bitv: bitv }
1224 /// Returns the capacity in bits for this bit vector. Inserting any
1225 /// element less than this amount will not trigger a resizing.
1230 /// use std::collections::BitvSet;
1232 /// let mut s = BitvSet::with_capacity(100);
1233 /// assert!(s.capacity() >= 100);
1237 pub fn capacity(&self) -> uint {
1238 self.bitv.capacity()
1241 /// Reserves capacity for the given `BitvSet` to contain `len` distinct elements. In the case
1242 /// of `BitvSet` this means reallocations will not occur as long as all inserted elements
1243 /// are less than `len`.
1245 /// The collection may reserve more space to avoid frequent reallocations.
1251 /// use std::collections::BitvSet;
1253 /// let mut s = BitvSet::new();
1254 /// s.reserve_len(10);
1255 /// assert!(s.capacity() >= 10);
1258 pub fn reserve_len(&mut self, len: uint) {
1259 let cur_len = self.bitv.len();
1261 self.bitv.reserve(len - cur_len);
1265 /// Reserves the minimum capacity for the given `BitvSet` to contain `len` distinct elements.
1266 /// In the case of `BitvSet` this means reallocations will not occur as long as all inserted
1267 /// elements are less than `len`.
1269 /// Note that the allocator may give the collection more space than it requests. Therefore
1270 /// capacity can not be relied upon to be precisely minimal. Prefer `reserve_len` if future
1271 /// insertions are expected.
1277 /// use std::collections::BitvSet;
1279 /// let mut s = BitvSet::new();
1280 /// s.reserve_len_exact(10);
1281 /// assert!(s.capacity() >= 10);
1284 pub fn reserve_len_exact(&mut self, len: uint) {
1285 let cur_len = self.bitv.len();
1287 self.bitv.reserve_exact(len - cur_len);
1292 /// Consumes this set to return the underlying bit vector.
1297 /// use std::collections::BitvSet;
1299 /// let mut s = BitvSet::new();
1303 /// let bv = s.into_bitv();
1308 pub fn into_bitv(self) -> Bitv {
1312 /// Returns a reference to the underlying bit vector.
1317 /// use std::collections::BitvSet;
1319 /// let mut s = BitvSet::new();
1322 /// let bv = s.get_ref();
1323 /// assert_eq!(bv[0], true);
1326 pub fn get_ref(&self) -> &Bitv {
1331 fn other_op<F>(&mut self, other: &BitvSet, mut f: F) where F: FnMut(u32, u32) -> u32 {
1333 let self_bitv = &mut self.bitv;
1334 let other_bitv = &other.bitv;
1336 let self_len = self_bitv.len();
1337 let other_len = other_bitv.len();
1339 // Expand the vector if necessary
1340 if self_len < other_len {
1341 self_bitv.grow(other_len - self_len, false);
1344 // virtually pad other with 0's for equal lengths
1345 let mut other_words = {
1346 let (_, result) = match_words(self_bitv, other_bitv);
1350 // Apply values found in other
1351 for (i, w) in other_words {
1352 let old = self_bitv.storage[i];
1353 let new = f(old, w);
1354 self_bitv.storage[i] = new;
1358 /// Truncates the underlying vector to the least length required.
1363 /// use std::collections::BitvSet;
1365 /// let mut s = BitvSet::new();
1366 /// s.insert(32183231);
1367 /// s.remove(&32183231);
1369 /// // Internal storage will probably be bigger than necessary
1370 /// println!("old capacity: {}", s.capacity());
1372 /// // Now should be smaller
1373 /// s.shrink_to_fit();
1374 /// println!("new capacity: {}", s.capacity());
1378 pub fn shrink_to_fit(&mut self) {
1379 let bitv = &mut self.bitv;
1380 // Obtain original length
1381 let old_len = bitv.storage.len();
1382 // Obtain coarse trailing zero length
1383 let n = bitv.storage.iter().rev().take_while(|&&n| n == 0).count();
1385 let trunc_len = cmp::max(old_len - n, 1);
1386 bitv.storage.truncate(trunc_len);
1387 bitv.nbits = trunc_len * u32::BITS;
1390 /// Iterator over each u32 stored in the `BitvSet`.
1395 /// use std::collections::{Bitv, BitvSet};
1397 /// let s = BitvSet::from_bitv(Bitv::from_bytes(&[0b01001010]));
1399 /// // Print 1, 4, 6 in arbitrary order
1400 /// for x in s.iter() {
1401 /// println!("{}", x);
1406 pub fn iter(&self) -> bitv_set::Iter {
1407 SetIter {set: self, next_idx: 0u}
1410 /// Iterator over each u32 stored in `self` union `other`.
1411 /// See [union_with](#method.union_with) for an efficient in-place version.
1416 /// use std::collections::{Bitv, BitvSet};
1418 /// let a = BitvSet::from_bitv(Bitv::from_bytes(&[0b01101000]));
1419 /// let b = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100000]));
1421 /// // Print 0, 1, 2, 4 in arbitrary order
1422 /// for x in a.union(&b) {
1423 /// println!("{}", x);
1428 pub fn union<'a>(&'a self, other: &'a BitvSet) -> Union<'a> {
1429 fn or(w1: u32, w2: u32) -> u32 { w1 | w2 }
1431 Union(TwoBitPositions {
1440 /// Iterator over each uint stored in `self` intersect `other`.
1441 /// See [intersect_with](#method.intersect_with) for an efficient in-place version.
1446 /// use std::collections::{Bitv, BitvSet};
1448 /// let a = BitvSet::from_bitv(Bitv::from_bytes(&[0b01101000]));
1449 /// let b = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100000]));
1452 /// for x in a.intersection(&b) {
1453 /// println!("{}", x);
1458 pub fn intersection<'a>(&'a self, other: &'a BitvSet) -> Intersection<'a> {
1459 fn bitand(w1: u32, w2: u32) -> u32 { w1 & w2 }
1460 let min = cmp::min(self.bitv.len(), other.bitv.len());
1461 Intersection(TwoBitPositions {
1470 /// Iterator over each uint stored in the `self` setminus `other`.
1471 /// See [difference_with](#method.difference_with) for an efficient in-place version.
1476 /// use std::collections::{BitvSet, Bitv};
1478 /// let a = BitvSet::from_bitv(Bitv::from_bytes(&[0b01101000]));
1479 /// let b = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100000]));
1481 /// // Print 1, 4 in arbitrary order
1482 /// for x in a.difference(&b) {
1483 /// println!("{}", x);
1486 /// // Note that difference is not symmetric,
1487 /// // and `b - a` means something else.
1488 /// // This prints 0
1489 /// for x in b.difference(&a) {
1490 /// println!("{}", x);
1495 pub fn difference<'a>(&'a self, other: &'a BitvSet) -> Difference<'a> {
1496 fn diff(w1: u32, w2: u32) -> u32 { w1 & !w2 }
1498 Difference(TwoBitPositions {
1507 /// Iterator over each u32 stored in the symmetric difference of `self` and `other`.
1508 /// See [symmetric_difference_with](#method.symmetric_difference_with) for
1509 /// an efficient in-place version.
1514 /// use std::collections::{BitvSet, Bitv};
1516 /// let a = BitvSet::from_bitv(Bitv::from_bytes(&[0b01101000]));
1517 /// let b = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100000]));
1519 /// // Print 0, 1, 4 in arbitrary order
1520 /// for x in a.symmetric_difference(&b) {
1521 /// println!("{}", x);
1526 pub fn symmetric_difference<'a>(&'a self, other: &'a BitvSet) -> SymmetricDifference<'a> {
1527 fn bitxor(w1: u32, w2: u32) -> u32 { w1 ^ w2 }
1529 SymmetricDifference(TwoBitPositions {
1538 /// Unions in-place with the specified other bit vector.
1543 /// use std::collections::{BitvSet, Bitv};
1545 /// let a = 0b01101000;
1546 /// let b = 0b10100000;
1547 /// let res = 0b11101000;
1549 /// let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[a]));
1550 /// let b = BitvSet::from_bitv(Bitv::from_bytes(&[b]));
1551 /// let res = BitvSet::from_bitv(Bitv::from_bytes(&[res]));
1553 /// a.union_with(&b);
1554 /// assert_eq!(a, res);
1557 pub fn union_with(&mut self, other: &BitvSet) {
1558 self.other_op(other, |w1, w2| w1 | w2);
1561 /// Intersects in-place with the specified other bit vector.
1566 /// use std::collections::{BitvSet, Bitv};
1568 /// let a = 0b01101000;
1569 /// let b = 0b10100000;
1570 /// let res = 0b00100000;
1572 /// let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[a]));
1573 /// let b = BitvSet::from_bitv(Bitv::from_bytes(&[b]));
1574 /// let res = BitvSet::from_bitv(Bitv::from_bytes(&[res]));
1576 /// a.intersect_with(&b);
1577 /// assert_eq!(a, res);
1580 pub fn intersect_with(&mut self, other: &BitvSet) {
1581 self.other_op(other, |w1, w2| w1 & w2);
1584 /// Makes this bit vector the difference with the specified other bit vector
1590 /// use std::collections::{BitvSet, Bitv};
1592 /// let a = 0b01101000;
1593 /// let b = 0b10100000;
1594 /// let a_b = 0b01001000; // a - b
1595 /// let b_a = 0b10000000; // b - a
1597 /// let mut bva = BitvSet::from_bitv(Bitv::from_bytes(&[a]));
1598 /// let bvb = BitvSet::from_bitv(Bitv::from_bytes(&[b]));
1599 /// let bva_b = BitvSet::from_bitv(Bitv::from_bytes(&[a_b]));
1600 /// let bvb_a = BitvSet::from_bitv(Bitv::from_bytes(&[b_a]));
1602 /// bva.difference_with(&bvb);
1603 /// assert_eq!(bva, bva_b);
1605 /// let bva = BitvSet::from_bitv(Bitv::from_bytes(&[a]));
1606 /// let mut bvb = BitvSet::from_bitv(Bitv::from_bytes(&[b]));
1608 /// bvb.difference_with(&bva);
1609 /// assert_eq!(bvb, bvb_a);
1612 pub fn difference_with(&mut self, other: &BitvSet) {
1613 self.other_op(other, |w1, w2| w1 & !w2);
1616 /// Makes this bit vector the symmetric difference with the specified other
1617 /// bit vector in-place.
1622 /// use std::collections::{BitvSet, Bitv};
1624 /// let a = 0b01101000;
1625 /// let b = 0b10100000;
1626 /// let res = 0b11001000;
1628 /// let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[a]));
1629 /// let b = BitvSet::from_bitv(Bitv::from_bytes(&[b]));
1630 /// let res = BitvSet::from_bitv(Bitv::from_bytes(&[res]));
1632 /// a.symmetric_difference_with(&b);
1633 /// assert_eq!(a, res);
1636 pub fn symmetric_difference_with(&mut self, other: &BitvSet) {
1637 self.other_op(other, |w1, w2| w1 ^ w2);
1640 /// Return the number of set bits in this set.
1643 pub fn len(&self) -> uint {
1644 self.bitv.blocks().fold(0, |acc, n| acc + n.count_ones())
1647 /// Returns whether there are no bits set in this set
1650 pub fn is_empty(&self) -> bool {
1654 /// Clears all bits in this set
1657 pub fn clear(&mut self) {
1661 /// Returns `true` if this set contains the specified integer.
1664 pub fn contains(&self, value: &uint) -> bool {
1665 let bitv = &self.bitv;
1666 *value < bitv.nbits && bitv[*value]
1669 /// Returns `true` if the set has no elements in common with `other`.
1670 /// This is equivalent to checking for an empty intersection.
1673 pub fn is_disjoint(&self, other: &BitvSet) -> bool {
1674 self.intersection(other).next().is_none()
1677 /// Returns `true` if the set is a subset of another.
1680 pub fn is_subset(&self, other: &BitvSet) -> bool {
1681 let self_bitv = &self.bitv;
1682 let other_bitv = &other.bitv;
1683 let other_blocks = blocks_for_bits(other_bitv.len());
1685 // Check that `self` intersect `other` is self
1686 self_bitv.blocks().zip(other_bitv.blocks()).all(|(w1, w2)| w1 & w2 == w1) &&
1687 // Make sure if `self` has any more blocks than `other`, they're all 0
1688 self_bitv.blocks().skip(other_blocks).all(|w| w == 0)
1691 /// Returns `true` if the set is a superset of another.
1694 pub fn is_superset(&self, other: &BitvSet) -> bool {
1695 other.is_subset(self)
1698 /// Adds a value to the set. Returns `true` if the value was not already
1699 /// present in the set.
1701 pub fn insert(&mut self, value: uint) -> bool {
1702 if self.contains(&value) {
1706 // Ensure we have enough space to hold the new element
1707 let len = self.bitv.len();
1709 self.bitv.grow(value - len + 1, false)
1712 self.bitv.set(value, true);
1716 /// Removes a value from the set. Returns `true` if the value was
1717 /// present in the set.
1719 pub fn remove(&mut self, value: &uint) -> bool {
1720 if !self.contains(value) {
1724 self.bitv.set(*value, false);
1730 impl fmt::Show for BitvSet {
1731 fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
1732 try!(write!(fmt, "BitvSet {{"));
1733 let mut first = true;
1734 for n in self.iter() {
1736 try!(write!(fmt, ", "));
1738 try!(write!(fmt, "{:?}", n));
1745 impl<S: hash::Writer + hash::Hasher> hash::Hash<S> for BitvSet {
1746 fn hash(&self, state: &mut S) {
1747 for pos in self.iter() {
1753 /// An iterator for `BitvSet`.
1756 pub struct SetIter<'a> {
1761 /// An iterator combining two `BitvSet` iterators.
1763 struct TwoBitPositions<'a> {
1766 merge: fn(u32, u32) -> u32,
1772 pub struct Union<'a>(TwoBitPositions<'a>);
1774 pub struct Intersection<'a>(Take<TwoBitPositions<'a>>);
1776 pub struct Difference<'a>(TwoBitPositions<'a>);
1778 pub struct SymmetricDifference<'a>(TwoBitPositions<'a>);
1781 impl<'a> Iterator for SetIter<'a> {
1784 fn next(&mut self) -> Option<uint> {
1785 while self.next_idx < self.set.bitv.len() {
1786 let idx = self.next_idx;
1789 if self.set.contains(&idx) {
1798 fn size_hint(&self) -> (uint, Option<uint>) {
1799 (0, Some(self.set.bitv.len() - self.next_idx))
1804 impl<'a> Iterator for TwoBitPositions<'a> {
1807 fn next(&mut self) -> Option<uint> {
1808 while self.next_idx < self.set.bitv.len() ||
1809 self.next_idx < self.other.bitv.len() {
1810 let bit_idx = self.next_idx % u32::BITS;
1812 let s_bitv = &self.set.bitv;
1813 let o_bitv = &self.other.bitv;
1814 // Merging the two words is a bit of an awkward dance since
1815 // one Bitv might be longer than the other
1816 let word_idx = self.next_idx / u32::BITS;
1817 let w1 = if word_idx < s_bitv.storage.len() {
1818 s_bitv.storage[word_idx]
1820 let w2 = if word_idx < o_bitv.storage.len() {
1821 o_bitv.storage[word_idx]
1823 self.current_word = (self.merge)(w1, w2);
1827 if self.current_word & (1 << bit_idx) != 0 {
1828 return Some(self.next_idx - 1);
1835 fn size_hint(&self) -> (uint, Option<uint>) {
1836 let cap = cmp::max(self.set.bitv.len(), self.other.bitv.len());
1837 (0, Some(cap - self.next_idx))
1842 impl<'a> Iterator for Union<'a> {
1845 #[inline] fn next(&mut self) -> Option<uint> { self.0.next() }
1846 #[inline] fn size_hint(&self) -> (uint, Option<uint>) { self.0.size_hint() }
1850 impl<'a> Iterator for Intersection<'a> {
1853 #[inline] fn next(&mut self) -> Option<uint> { self.0.next() }
1854 #[inline] fn size_hint(&self) -> (uint, Option<uint>) { self.0.size_hint() }
1858 impl<'a> Iterator for Difference<'a> {
1861 #[inline] fn next(&mut self) -> Option<uint> { self.0.next() }
1862 #[inline] fn size_hint(&self) -> (uint, Option<uint>) { self.0.size_hint() }
1866 impl<'a> Iterator for SymmetricDifference<'a> {
1869 #[inline] fn next(&mut self) -> Option<uint> { self.0.next() }
1870 #[inline] fn size_hint(&self) -> (uint, Option<uint>) { self.0.size_hint() }
1883 let zerolen = Bitv::new();
1884 assert_eq!(format!("{:?}", zerolen), "");
1886 let eightbits = Bitv::from_elem(8u, false);
1887 assert_eq!(format!("{:?}", eightbits), "00000000")
1891 fn test_0_elements() {
1892 let act = Bitv::new();
1893 let exp = Vec::new();
1894 assert!(act.eq_vec(exp.as_slice()));
1895 assert!(act.none() && act.all());
1899 fn test_1_element() {
1900 let mut act = Bitv::from_elem(1u, false);
1901 assert!(act.eq_vec(&[false]));
1902 assert!(act.none() && !act.all());
1903 act = Bitv::from_elem(1u, true);
1904 assert!(act.eq_vec(&[true]));
1905 assert!(!act.none() && act.all());
1909 fn test_2_elements() {
1910 let mut b = Bitv::from_elem(2, false);
1913 assert_eq!(format!("{:?}", b), "10");
1914 assert!(!b.none() && !b.all());
1918 fn test_10_elements() {
1922 act = Bitv::from_elem(10u, false);
1923 assert!((act.eq_vec(
1924 &[false, false, false, false, false, false, false, false, false, false])));
1925 assert!(act.none() && !act.all());
1928 act = Bitv::from_elem(10u, true);
1929 assert!((act.eq_vec(&[true, true, true, true, true, true, true, true, true, true])));
1930 assert!(!act.none() && act.all());
1933 act = Bitv::from_elem(10u, false);
1939 assert!((act.eq_vec(&[true, true, true, true, true, false, false, false, false, false])));
1940 assert!(!act.none() && !act.all());
1943 act = Bitv::from_elem(10u, false);
1949 assert!((act.eq_vec(&[false, false, false, false, false, true, true, true, true, true])));
1950 assert!(!act.none() && !act.all());
1953 act = Bitv::from_elem(10u, false);
1958 assert!((act.eq_vec(&[true, false, false, true, false, false, true, false, false, true])));
1959 assert!(!act.none() && !act.all());
1963 fn test_31_elements() {
1967 act = Bitv::from_elem(31u, false);
1969 &[false, false, false, false, false, false, false, false, false, false, false,
1970 false, false, false, false, false, false, false, false, false, false, false,
1971 false, false, false, false, false, false, false, false, false]));
1972 assert!(act.none() && !act.all());
1975 act = Bitv::from_elem(31u, true);
1977 &[true, true, true, true, true, true, true, true, true, true, true, true, true,
1978 true, true, true, true, true, true, true, true, true, true, true, true, true,
1979 true, true, true, true, true]));
1980 assert!(!act.none() && act.all());
1983 act = Bitv::from_elem(31u, false);
1993 &[true, true, true, true, true, true, true, true, false, false, false, false, false,
1994 false, false, false, false, false, false, false, false, false, false, false,
1995 false, false, false, false, false, false, false]));
1996 assert!(!act.none() && !act.all());
1999 act = Bitv::from_elem(31u, false);
2009 &[false, false, false, false, false, false, false, false, false, false, false,
2010 false, false, false, false, false, true, true, true, true, true, true, true, true,
2011 false, false, false, false, false, false, false]));
2012 assert!(!act.none() && !act.all());
2015 act = Bitv::from_elem(31u, false);
2024 &[false, false, false, false, false, false, false, false, false, false, false,
2025 false, false, false, false, false, false, false, false, false, false, false,
2026 false, false, true, true, true, true, true, true, true]));
2027 assert!(!act.none() && !act.all());
2030 act = Bitv::from_elem(31u, false);
2035 &[false, false, false, true, false, false, false, false, false, false, false, false,
2036 false, false, false, false, false, true, false, false, false, false, false, false,
2037 false, false, false, false, false, false, true]));
2038 assert!(!act.none() && !act.all());
2042 fn test_32_elements() {
2046 act = Bitv::from_elem(32u, false);
2048 &[false, false, false, false, false, false, false, false, false, false, false,
2049 false, false, false, false, false, false, false, false, false, false, false,
2050 false, false, false, false, false, false, false, false, false, false]));
2051 assert!(act.none() && !act.all());
2054 act = Bitv::from_elem(32u, true);
2056 &[true, true, true, true, true, true, true, true, true, true, true, true, true,
2057 true, true, true, true, true, true, true, true, true, true, true, true, true,
2058 true, true, true, true, true, true]));
2059 assert!(!act.none() && act.all());
2062 act = Bitv::from_elem(32u, false);
2072 &[true, true, true, true, true, true, true, true, false, false, false, false, false,
2073 false, false, false, false, false, false, false, false, false, false, false,
2074 false, false, false, false, false, false, false, false]));
2075 assert!(!act.none() && !act.all());
2078 act = Bitv::from_elem(32u, false);
2088 &[false, false, false, false, false, false, false, false, false, false, false,
2089 false, false, false, false, false, true, true, true, true, true, true, true, true,
2090 false, false, false, false, false, false, false, false]));
2091 assert!(!act.none() && !act.all());
2094 act = Bitv::from_elem(32u, false);
2104 &[false, false, false, false, false, false, false, false, false, false, false,
2105 false, false, false, false, false, false, false, false, false, false, false,
2106 false, false, true, true, true, true, true, true, true, true]));
2107 assert!(!act.none() && !act.all());
2110 act = Bitv::from_elem(32u, false);
2116 &[false, false, false, true, false, false, false, false, false, false, false, false,
2117 false, false, false, false, false, true, false, false, false, false, false, false,
2118 false, false, false, false, false, false, true, true]));
2119 assert!(!act.none() && !act.all());
2123 fn test_33_elements() {
2127 act = Bitv::from_elem(33u, false);
2129 &[false, false, false, false, false, false, false, false, false, false, false,
2130 false, false, false, false, false, false, false, false, false, false, false,
2131 false, false, false, false, false, false, false, false, false, false, false]));
2132 assert!(act.none() && !act.all());
2135 act = Bitv::from_elem(33u, true);
2137 &[true, true, true, true, true, true, true, true, true, true, true, true, true,
2138 true, true, true, true, true, true, true, true, true, true, true, true, true,
2139 true, true, true, true, true, true, true]));
2140 assert!(!act.none() && act.all());
2143 act = Bitv::from_elem(33u, false);
2153 &[true, true, true, true, true, true, true, true, false, false, false, false, false,
2154 false, false, false, false, false, false, false, false, false, false, false,
2155 false, false, false, false, false, false, false, false, false]));
2156 assert!(!act.none() && !act.all());
2159 act = Bitv::from_elem(33u, false);
2169 &[false, false, false, false, false, false, false, false, false, false, false,
2170 false, false, false, false, false, true, true, true, true, true, true, true, true,
2171 false, false, false, false, false, false, false, false, false]));
2172 assert!(!act.none() && !act.all());
2175 act = Bitv::from_elem(33u, false);
2185 &[false, false, false, false, false, false, false, false, false, false, false,
2186 false, false, false, false, false, false, false, false, false, false, false,
2187 false, false, true, true, true, true, true, true, true, true, false]));
2188 assert!(!act.none() && !act.all());
2191 act = Bitv::from_elem(33u, false);
2198 &[false, false, false, true, false, false, false, false, false, false, false, false,
2199 false, false, false, false, false, true, false, false, false, false, false, false,
2200 false, false, false, false, false, false, true, true, true]));
2201 assert!(!act.none() && !act.all());
2205 fn test_equal_differing_sizes() {
2206 let v0 = Bitv::from_elem(10u, false);
2207 let v1 = Bitv::from_elem(11u, false);
2212 fn test_equal_greatly_differing_sizes() {
2213 let v0 = Bitv::from_elem(10u, false);
2214 let v1 = Bitv::from_elem(110u, false);
2219 fn test_equal_sneaky_small() {
2220 let mut a = Bitv::from_elem(1, false);
2223 let mut b = Bitv::from_elem(1, true);
2230 fn test_equal_sneaky_big() {
2231 let mut a = Bitv::from_elem(100, false);
2232 for i in range(0u, 100) {
2236 let mut b = Bitv::from_elem(100, true);
2237 for i in range(0u, 100) {
2245 fn test_from_bytes() {
2246 let bitv = Bitv::from_bytes(&[0b10110110, 0b00000000, 0b11111111]);
2247 let str = concat!("10110110", "00000000", "11111111");
2248 assert_eq!(format!("{:?}", bitv), str);
2252 fn test_to_bytes() {
2253 let mut bv = Bitv::from_elem(3, true);
2255 assert_eq!(bv.to_bytes(), vec!(0b10100000));
2257 let mut bv = Bitv::from_elem(9, false);
2260 assert_eq!(bv.to_bytes(), vec!(0b00100000, 0b10000000));
2264 fn test_from_bools() {
2265 let bools = vec![true, false, true, true];
2266 let bitv: Bitv = bools.iter().map(|n| *n).collect();
2267 assert_eq!(format!("{:?}", bitv), "1011");
2271 fn test_to_bools() {
2272 let bools = vec!(false, false, true, false, false, true, true, false);
2273 assert_eq!(Bitv::from_bytes(&[0b00100110]).iter().collect::<Vec<bool>>(), bools);
2277 fn test_bitv_iterator() {
2278 let bools = vec![true, false, true, true];
2279 let bitv: Bitv = bools.iter().map(|n| *n).collect();
2281 assert_eq!(bitv.iter().collect::<Vec<bool>>(), bools);
2283 let long = range(0, 10000).map(|i| i % 2 == 0).collect::<Vec<_>>();
2284 let bitv: Bitv = long.iter().map(|n| *n).collect();
2285 assert_eq!(bitv.iter().collect::<Vec<bool>>(), long)
2289 fn test_small_difference() {
2290 let mut b1 = Bitv::from_elem(3, false);
2291 let mut b2 = Bitv::from_elem(3, false);
2296 assert!(b1.difference(&b2));
2303 fn test_big_difference() {
2304 let mut b1 = Bitv::from_elem(100, false);
2305 let mut b2 = Bitv::from_elem(100, false);
2310 assert!(b1.difference(&b2));
2317 fn test_small_clear() {
2318 let mut b = Bitv::from_elem(14, true);
2319 assert!(!b.none() && b.all());
2321 assert!(b.none() && !b.all());
2325 fn test_big_clear() {
2326 let mut b = Bitv::from_elem(140, true);
2327 assert!(!b.none() && b.all());
2329 assert!(b.none() && !b.all());
2334 let mut a = Bitv::from_elem(5u, false);
2335 let mut b = Bitv::from_elem(5u, false);
2337 assert!(!(a < b) && !(b < a));
2343 assert!(!(a < b) && b < a);
2350 let mut a = Bitv::from_elem(5u, false);
2351 let mut b = Bitv::from_elem(5u, false);
2353 assert!(a <= b && a >= b);
2355 assert!(a > b && a >= b);
2356 assert!(b < a && b <= a);
2359 assert!(b > a && b >= a);
2360 assert!(a < b && a <= b);
2365 fn test_small_bitv_tests() {
2366 let v = Bitv::from_bytes(&[0]);
2371 let v = Bitv::from_bytes(&[0b00010100]);
2376 let v = Bitv::from_bytes(&[0xFF]);
2383 fn test_big_bitv_tests() {
2384 let v = Bitv::from_bytes(&[ // 88 bits
2392 let v = Bitv::from_bytes(&[ // 88 bits
2393 0, 0, 0b00010100, 0,
2394 0, 0, 0, 0b00110100,
2400 let v = Bitv::from_bytes(&[ // 88 bits
2401 0xFF, 0xFF, 0xFF, 0xFF,
2402 0xFF, 0xFF, 0xFF, 0xFF,
2410 fn test_bitv_push_pop() {
2411 let mut s = Bitv::from_elem(5 * u32::BITS - 2, false);
2412 assert_eq!(s.len(), 5 * u32::BITS - 2);
2413 assert_eq!(s[5 * u32::BITS - 3], false);
2416 assert_eq!(s[5 * u32::BITS - 2], true);
2417 assert_eq!(s[5 * u32::BITS - 1], true);
2418 // Here the internal vector will need to be extended
2420 assert_eq!(s[5 * u32::BITS], false);
2422 assert_eq!(s[5 * u32::BITS + 1], false);
2423 assert_eq!(s.len(), 5 * u32::BITS + 2);
2425 assert_eq!(s.pop(), Some(false));
2426 assert_eq!(s.pop(), Some(false));
2427 assert_eq!(s.pop(), Some(true));
2428 assert_eq!(s.pop(), Some(true));
2429 assert_eq!(s.len(), 5 * u32::BITS - 2);
2433 fn test_bitv_truncate() {
2434 let mut s = Bitv::from_elem(5 * u32::BITS, true);
2436 assert_eq!(s, Bitv::from_elem(5 * u32::BITS, true));
2437 assert_eq!(s.len(), 5 * u32::BITS);
2438 s.truncate(4 * u32::BITS);
2439 assert_eq!(s, Bitv::from_elem(4 * u32::BITS, true));
2440 assert_eq!(s.len(), 4 * u32::BITS);
2441 // Truncating to a size > s.len() should be a noop
2442 s.truncate(5 * u32::BITS);
2443 assert_eq!(s, Bitv::from_elem(4 * u32::BITS, true));
2444 assert_eq!(s.len(), 4 * u32::BITS);
2445 s.truncate(3 * u32::BITS - 10);
2446 assert_eq!(s, Bitv::from_elem(3 * u32::BITS - 10, true));
2447 assert_eq!(s.len(), 3 * u32::BITS - 10);
2449 assert_eq!(s, Bitv::from_elem(0, true));
2450 assert_eq!(s.len(), 0);
2454 fn test_bitv_reserve() {
2455 let mut s = Bitv::from_elem(5 * u32::BITS, true);
2457 assert!(s.capacity() >= 5 * u32::BITS);
2458 s.reserve(2 * u32::BITS);
2459 assert!(s.capacity() >= 7 * u32::BITS);
2460 s.reserve(7 * u32::BITS);
2461 assert!(s.capacity() >= 12 * u32::BITS);
2462 s.reserve_exact(7 * u32::BITS);
2463 assert!(s.capacity() >= 12 * u32::BITS);
2464 s.reserve(7 * u32::BITS + 1);
2465 assert!(s.capacity() >= 12 * u32::BITS + 1);
2466 // Check that length hasn't changed
2467 assert_eq!(s.len(), 5 * u32::BITS);
2471 assert_eq!(s[5 * u32::BITS - 1], true);
2472 assert_eq!(s[5 * u32::BITS - 0], true);
2473 assert_eq!(s[5 * u32::BITS + 1], false);
2474 assert_eq!(s[5 * u32::BITS + 2], true);
2478 fn test_bitv_grow() {
2479 let mut bitv = Bitv::from_bytes(&[0b10110110, 0b00000000, 0b10101010]);
2480 bitv.grow(32, true);
2481 assert_eq!(bitv, Bitv::from_bytes(&[0b10110110, 0b00000000, 0b10101010,
2482 0xFF, 0xFF, 0xFF, 0xFF]));
2483 bitv.grow(64, false);
2484 assert_eq!(bitv, Bitv::from_bytes(&[0b10110110, 0b00000000, 0b10101010,
2485 0xFF, 0xFF, 0xFF, 0xFF, 0, 0, 0, 0, 0, 0, 0, 0]));
2486 bitv.grow(16, true);
2487 assert_eq!(bitv, Bitv::from_bytes(&[0b10110110, 0b00000000, 0b10101010,
2488 0xFF, 0xFF, 0xFF, 0xFF, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF]));
2492 fn test_bitv_extend() {
2493 let mut bitv = Bitv::from_bytes(&[0b10110110, 0b00000000, 0b11111111]);
2494 let ext = Bitv::from_bytes(&[0b01001001, 0b10010010, 0b10111101]);
2495 bitv.extend(ext.iter());
2496 assert_eq!(bitv, Bitv::from_bytes(&[0b10110110, 0b00000000, 0b11111111,
2497 0b01001001, 0b10010010, 0b10111101]));
2506 use std::prelude::v1::*;
2510 use test::{Bencher, black_box};
2514 static BENCH_BITS : uint = 1 << 14;
2516 fn rng() -> rand::IsaacRng {
2517 let seed: &[_] = &[1, 2, 3, 4, 5, 6, 7, 8, 9, 0];
2518 rand::SeedableRng::from_seed(seed)
2522 fn bench_uint_small(b: &mut Bencher) {
2524 let mut bitv = 0 as uint;
2526 for _ in range(0u, 100) {
2527 bitv |= 1 << ((r.next_u32() as uint) % u32::BITS);
2534 fn bench_bitv_set_big_fixed(b: &mut Bencher) {
2536 let mut bitv = Bitv::from_elem(BENCH_BITS, false);
2538 for _ in range(0u, 100) {
2539 bitv.set((r.next_u32() as uint) % BENCH_BITS, true);
2546 fn bench_bitv_set_big_variable(b: &mut Bencher) {
2548 let mut bitv = Bitv::from_elem(BENCH_BITS, false);
2550 for _ in range(0u, 100) {
2551 bitv.set((r.next_u32() as uint) % BENCH_BITS, r.gen());
2558 fn bench_bitv_set_small(b: &mut Bencher) {
2560 let mut bitv = Bitv::from_elem(u32::BITS, false);
2562 for _ in range(0u, 100) {
2563 bitv.set((r.next_u32() as uint) % u32::BITS, true);
2570 fn bench_bitv_big_union(b: &mut Bencher) {
2571 let mut b1 = Bitv::from_elem(BENCH_BITS, false);
2572 let b2 = Bitv::from_elem(BENCH_BITS, false);
2579 fn bench_bitv_small_iter(b: &mut Bencher) {
2580 let bitv = Bitv::from_elem(u32::BITS, false);
2583 for _ in range(0u, 10) {
2584 for pres in bitv.iter() {
2585 sum += pres as uint;
2593 fn bench_bitv_big_iter(b: &mut Bencher) {
2594 let bitv = Bitv::from_elem(BENCH_BITS, false);
2597 for pres in bitv.iter() {
2598 sum += pres as uint;
2614 use std::iter::range_step;
2616 use super::{Bitv, BitvSet};
2619 fn test_bitv_set_show() {
2620 let mut s = BitvSet::new();
2625 assert_eq!("BitvSet {1u, 2u, 10u, 50u}", format!("{:?}", s));
2629 fn test_bitv_set_from_uints() {
2630 let uints = vec![0, 2, 2, 3];
2631 let a: BitvSet = uints.into_iter().collect();
2632 let mut b = BitvSet::new();
2640 fn test_bitv_set_iterator() {
2641 let uints = vec![0, 2, 2, 3];
2642 let bitv: BitvSet = uints.into_iter().collect();
2644 let idxs: Vec<uint> = bitv.iter().collect();
2645 assert_eq!(idxs, vec![0, 2, 3]);
2647 let long: BitvSet = range(0u, 10000).filter(|&n| n % 2 == 0).collect();
2648 let real = range_step(0, 10000, 2).collect::<Vec<uint>>();
2650 let idxs: Vec<uint> = long.iter().collect();
2651 assert_eq!(idxs, real);
2655 fn test_bitv_set_frombitv_init() {
2656 let bools = [true, false];
2657 let lengths = [10, 64, 100];
2658 for &b in bools.iter() {
2659 for &l in lengths.iter() {
2660 let bitset = BitvSet::from_bitv(Bitv::from_elem(l, b));
2661 assert_eq!(bitset.contains(&1u), b);
2662 assert_eq!(bitset.contains(&(l-1u)), b);
2663 assert!(!bitset.contains(&l));
2669 fn test_bitv_masking() {
2670 let b = Bitv::from_elem(140, true);
2671 let mut bs = BitvSet::from_bitv(b);
2672 assert!(bs.contains(&139));
2673 assert!(!bs.contains(&140));
2674 assert!(bs.insert(150));
2675 assert!(!bs.contains(&140));
2676 assert!(!bs.contains(&149));
2677 assert!(bs.contains(&150));
2678 assert!(!bs.contains(&151));
2682 fn test_bitv_set_basic() {
2683 let mut b = BitvSet::new();
2684 assert!(b.insert(3));
2685 assert!(!b.insert(3));
2686 assert!(b.contains(&3));
2687 assert!(b.insert(4));
2688 assert!(!b.insert(4));
2689 assert!(b.contains(&3));
2690 assert!(b.insert(400));
2691 assert!(!b.insert(400));
2692 assert!(b.contains(&400));
2693 assert_eq!(b.len(), 3);
2697 fn test_bitv_set_intersection() {
2698 let mut a = BitvSet::new();
2699 let mut b = BitvSet::new();
2701 assert!(a.insert(11));
2702 assert!(a.insert(1));
2703 assert!(a.insert(3));
2704 assert!(a.insert(77));
2705 assert!(a.insert(103));
2706 assert!(a.insert(5));
2708 assert!(b.insert(2));
2709 assert!(b.insert(11));
2710 assert!(b.insert(77));
2711 assert!(b.insert(5));
2712 assert!(b.insert(3));
2714 let expected = [3, 5, 11, 77];
2715 let actual = a.intersection(&b).collect::<Vec<uint>>();
2716 assert_eq!(actual, expected);
2720 fn test_bitv_set_difference() {
2721 let mut a = BitvSet::new();
2722 let mut b = BitvSet::new();
2724 assert!(a.insert(1));
2725 assert!(a.insert(3));
2726 assert!(a.insert(5));
2727 assert!(a.insert(200));
2728 assert!(a.insert(500));
2730 assert!(b.insert(3));
2731 assert!(b.insert(200));
2733 let expected = [1, 5, 500];
2734 let actual = a.difference(&b).collect::<Vec<uint>>();
2735 assert_eq!(actual, expected);
2739 fn test_bitv_set_symmetric_difference() {
2740 let mut a = BitvSet::new();
2741 let mut b = BitvSet::new();
2743 assert!(a.insert(1));
2744 assert!(a.insert(3));
2745 assert!(a.insert(5));
2746 assert!(a.insert(9));
2747 assert!(a.insert(11));
2749 assert!(b.insert(3));
2750 assert!(b.insert(9));
2751 assert!(b.insert(14));
2752 assert!(b.insert(220));
2754 let expected = [1, 5, 11, 14, 220];
2755 let actual = a.symmetric_difference(&b).collect::<Vec<uint>>();
2756 assert_eq!(actual, expected);
2760 fn test_bitv_set_union() {
2761 let mut a = BitvSet::new();
2762 let mut b = BitvSet::new();
2763 assert!(a.insert(1));
2764 assert!(a.insert(3));
2765 assert!(a.insert(5));
2766 assert!(a.insert(9));
2767 assert!(a.insert(11));
2768 assert!(a.insert(160));
2769 assert!(a.insert(19));
2770 assert!(a.insert(24));
2771 assert!(a.insert(200));
2773 assert!(b.insert(1));
2774 assert!(b.insert(5));
2775 assert!(b.insert(9));
2776 assert!(b.insert(13));
2777 assert!(b.insert(19));
2779 let expected = [1, 3, 5, 9, 11, 13, 19, 24, 160, 200];
2780 let actual = a.union(&b).collect::<Vec<uint>>();
2781 assert_eq!(actual, expected);
2785 fn test_bitv_set_subset() {
2786 let mut set1 = BitvSet::new();
2787 let mut set2 = BitvSet::new();
2789 assert!(set1.is_subset(&set2)); // {} {}
2791 assert!(set1.is_subset(&set2)); // {} { 1 }
2793 assert!(set1.is_subset(&set2)); // {} { 1, 2 }
2795 assert!(set1.is_subset(&set2)); // { 2 } { 1, 2 }
2797 assert!(!set1.is_subset(&set2)); // { 2, 3 } { 1, 2 }
2799 assert!(set1.is_subset(&set2)); // { 2, 3 } { 1, 2, 3 }
2801 assert!(set1.is_subset(&set2)); // { 2, 3 } { 1, 2, 3, 4 }
2803 assert!(set1.is_subset(&set2)); // { 2, 3 } { 2, 3, 4 }
2805 assert!(!set1.is_subset(&set2)); // { 2, 3 } { 2, 4 }
2807 assert!(set1.is_subset(&set2)); // { 2 } { 2, 4 }
2811 fn test_bitv_set_is_disjoint() {
2812 let a = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2813 let b = BitvSet::from_bitv(Bitv::from_bytes(&[0b01000000]));
2814 let c = BitvSet::new();
2815 let d = BitvSet::from_bitv(Bitv::from_bytes(&[0b00110000]));
2817 assert!(!a.is_disjoint(&d));
2818 assert!(!d.is_disjoint(&a));
2820 assert!(a.is_disjoint(&b));
2821 assert!(a.is_disjoint(&c));
2822 assert!(b.is_disjoint(&a));
2823 assert!(b.is_disjoint(&c));
2824 assert!(c.is_disjoint(&a));
2825 assert!(c.is_disjoint(&b));
2829 fn test_bitv_set_union_with() {
2830 //a should grow to include larger elements
2831 let mut a = BitvSet::new();
2833 let mut b = BitvSet::new();
2835 let expected = BitvSet::from_bitv(Bitv::from_bytes(&[0b10000100]));
2837 assert_eq!(a, expected);
2840 let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2841 let mut b = BitvSet::from_bitv(Bitv::from_bytes(&[0b01100010]));
2845 assert_eq!(a.len(), 4);
2846 assert_eq!(b.len(), 4);
2850 fn test_bitv_set_intersect_with() {
2851 // Explicitly 0'ed bits
2852 let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2853 let mut b = BitvSet::from_bitv(Bitv::from_bytes(&[0b00000000]));
2855 a.intersect_with(&b);
2856 b.intersect_with(&c);
2857 assert!(a.is_empty());
2858 assert!(b.is_empty());
2860 // Uninitialized bits should behave like 0's
2861 let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2862 let mut b = BitvSet::new();
2864 a.intersect_with(&b);
2865 b.intersect_with(&c);
2866 assert!(a.is_empty());
2867 assert!(b.is_empty());
2870 let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2871 let mut b = BitvSet::from_bitv(Bitv::from_bytes(&[0b01100010]));
2873 a.intersect_with(&b);
2874 b.intersect_with(&c);
2875 assert_eq!(a.len(), 2);
2876 assert_eq!(b.len(), 2);
2880 fn test_bitv_set_difference_with() {
2881 // Explicitly 0'ed bits
2882 let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[0b00000000]));
2883 let b = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2884 a.difference_with(&b);
2885 assert!(a.is_empty());
2887 // Uninitialized bits should behave like 0's
2888 let mut a = BitvSet::new();
2889 let b = BitvSet::from_bitv(Bitv::from_bytes(&[0b11111111]));
2890 a.difference_with(&b);
2891 assert!(a.is_empty());
2894 let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2895 let mut b = BitvSet::from_bitv(Bitv::from_bytes(&[0b01100010]));
2897 a.difference_with(&b);
2898 b.difference_with(&c);
2899 assert_eq!(a.len(), 1);
2900 assert_eq!(b.len(), 1);
2904 fn test_bitv_set_symmetric_difference_with() {
2905 //a should grow to include larger elements
2906 let mut a = BitvSet::new();
2909 let mut b = BitvSet::new();
2912 let expected = BitvSet::from_bitv(Bitv::from_bytes(&[0b10000100]));
2913 a.symmetric_difference_with(&b);
2914 assert_eq!(a, expected);
2916 let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2917 let b = BitvSet::new();
2919 a.symmetric_difference_with(&b);
2923 let mut a = BitvSet::from_bitv(Bitv::from_bytes(&[0b11100010]));
2924 let mut b = BitvSet::from_bitv(Bitv::from_bytes(&[0b01101010]));
2926 a.symmetric_difference_with(&b);
2927 b.symmetric_difference_with(&c);
2928 assert_eq!(a.len(), 2);
2929 assert_eq!(b.len(), 2);
2933 fn test_bitv_set_eq() {
2934 let a = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2935 let b = BitvSet::from_bitv(Bitv::from_bytes(&[0b00000000]));
2936 let c = BitvSet::new();
2947 fn test_bitv_set_cmp() {
2948 let a = BitvSet::from_bitv(Bitv::from_bytes(&[0b10100010]));
2949 let b = BitvSet::from_bitv(Bitv::from_bytes(&[0b00000000]));
2950 let c = BitvSet::new();
2952 assert_eq!(a.cmp(&b), Greater);
2953 assert_eq!(a.cmp(&c), Greater);
2954 assert_eq!(b.cmp(&a), Less);
2955 assert_eq!(b.cmp(&c), Equal);
2956 assert_eq!(c.cmp(&a), Less);
2957 assert_eq!(c.cmp(&b), Equal);
2961 fn test_bitv_remove() {
2962 let mut a = BitvSet::new();
2964 assert!(a.insert(1));
2965 assert!(a.remove(&1));
2967 assert!(a.insert(100));
2968 assert!(a.remove(&100));
2970 assert!(a.insert(1000));
2971 assert!(a.remove(&1000));
2976 fn test_bitv_clone() {
2977 let mut a = BitvSet::new();
2979 assert!(a.insert(1));
2980 assert!(a.insert(100));
2981 assert!(a.insert(1000));
2983 let mut b = a.clone();
2987 assert!(b.remove(&1));
2988 assert!(a.contains(&1));
2990 assert!(a.remove(&1000));
2991 assert!(b.contains(&1000));
3000 mod bitv_set_bench {
3001 use std::prelude::v1::*;
3005 use test::{Bencher, black_box};
3007 use super::{Bitv, BitvSet};
3009 static BENCH_BITS : uint = 1 << 14;
3011 fn rng() -> rand::IsaacRng {
3012 let seed: &[_] = &[1, 2, 3, 4, 5, 6, 7, 8, 9, 0];
3013 rand::SeedableRng::from_seed(seed)
3017 fn bench_bitvset_small(b: &mut Bencher) {
3019 let mut bitv = BitvSet::new();
3021 for _ in range(0u, 100) {
3022 bitv.insert((r.next_u32() as uint) % u32::BITS);
3029 fn bench_bitvset_big(b: &mut Bencher) {
3031 let mut bitv = BitvSet::new();
3033 for _ in range(0u, 100) {
3034 bitv.insert((r.next_u32() as uint) % BENCH_BITS);
3041 fn bench_bitvset_iter(b: &mut Bencher) {
3042 let bitv = BitvSet::from_bitv(Bitv::from_fn(BENCH_BITS,
3043 |idx| {idx % 3 == 0}));
3046 for idx in bitv.iter() {