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| author | Gareth Daniel Smith <garethdanielsmith@gmail.com> | 2012-09-02 18:04:38 +0100 |
|---|---|---|
| committer | Brian Anderson <banderson@mozilla.com> | 2012-09-04 13:23:23 -0700 |
| commit | 92f3b74db21c9cd6faaa013b716efb8535ba24d9 (patch) | |
| tree | 32f997198f071d68f03400091139f271f702fd49 | |
| parent | c5f674ae2a2c06f9e76af23d270fa22365aadc62 (diff) | |
| download | rust-92f3b74db21c9cd6faaa013b716efb8535ba24d9.tar.gz rust-92f3b74db21c9cd6faaa013b716efb8535ba24d9.zip | |
Use struct+impl syntax instead of the (deprecated) struct with embedded methods syntax. Also standardise the comment indentation and add some whitespace between items.
| -rw-r--r-- | src/libstd/bitv.rs | 336 |
1 files changed, 185 insertions, 151 deletions
diff --git a/src/libstd/bitv.rs b/src/libstd/bitv.rs index 64944d35888..c7e41f86e72 100644 --- a/src/libstd/bitv.rs +++ b/src/libstd/bitv.rs @@ -2,47 +2,57 @@ use vec::{to_mut, from_elem}; export Bitv, from_bytes, from_bools, from_fn; +struct SmallBitv { + /// only the lowest nbits of this value are used. the rest is undefined. + mut bits: u32 +} + +fn SmallBitv(bits: u32) -> SmallBitv { + SmallBitv {bits: bits} +} + /// a mask that has a 1 for each defined bit in a small_bitv, assuming n bits #[inline(always)] fn small_mask(nbits: uint) -> u32 { (1 << nbits) - 1 } -struct SmallBitv { - /// only the lowest nbits of this value are used. the rest is undefined. - let mut bits: u32; - new(bits: u32) { self.bits = bits; } - priv { - #[inline(always)] - fn bits_op(right_bits: u32, nbits: uint, f: fn(u32, u32) -> u32) - -> bool { - let mask = small_mask(nbits); - let old_b: u32 = self.bits; - let new_b = f(old_b, right_bits); - self.bits = new_b; - mask & old_b != mask & new_b - } +impl SmallBitv { + + #[inline(always)] + fn bits_op(right_bits: u32, nbits: uint, f: fn(u32, u32) -> u32) -> bool { + let mask = small_mask(nbits); + let old_b: u32 = self.bits; + let new_b = f(old_b, right_bits); + self.bits = new_b; + mask & old_b != mask & new_b } + #[inline(always)] fn union(s: &SmallBitv, nbits: uint) -> bool { self.bits_op(s.bits, nbits, |u1, u2| u1 | u2) } + #[inline(always)] fn intersect(s: &SmallBitv, nbits: uint) -> bool { self.bits_op(s.bits, nbits, |u1, u2| u1 & u2) } + #[inline(always)] fn become(s: &SmallBitv, nbits: uint) -> bool { self.bits_op(s.bits, nbits, |_u1, u2| u2) } + #[inline(always)] fn difference(s: &SmallBitv, nbits: uint) -> bool { self.bits_op(s.bits, nbits, |u1, u2| u1 ^ u2) } + #[inline(always)] pure fn get(i: uint) -> bool { (self.bits & (1 << i)) != 0 } + #[inline(always)] fn set(i: uint, x: bool) { if x { @@ -52,25 +62,41 @@ struct SmallBitv { self.bits &= !(1<<i as u32); } } + #[inline(always)] fn equals(b: &SmallBitv, nbits: uint) -> bool { let mask = small_mask(nbits); mask & self.bits == mask & b.bits } + #[inline(always)] fn clear() { self.bits = 0; } + #[inline(always)] fn set_all() { self.bits = !0; } + #[inline(always)] fn is_true(nbits: uint) -> bool { small_mask(nbits) & !self.bits == 0 } + #[inline(always)] fn is_false(nbits: uint) -> bool { small_mask(nbits) & self.bits == 0 } + #[inline(always)] fn invert() { self.bits = !self.bits; } + +} + +struct BigBitv { + // only mut b/c of clone and lack of other constructor + mut storage: ~[mut uint] +} + +fn BigBitv(-storage: ~[mut uint]) -> BigBitv { + BigBitv {storage: storage} } /** @@ -89,33 +115,27 @@ fn big_mask(nbits: uint, elem: uint) -> uint { } } -struct BigBitv { - // only mut b/c of clone and lack of other constructor - let mut storage: ~[mut uint]; - new(-storage: ~[mut uint]) { - self.storage <- storage; - } - priv { - #[inline(always)] - fn process(b: &BigBitv, nbits: uint, op: fn(uint, uint) -> uint) - -> bool { - let len = b.storage.len(); - assert (self.storage.len() == len); - let mut changed = false; - do uint::range(0, len) |i| { - let mask = big_mask(nbits, i); - let w0 = self.storage[i] & mask; - let w1 = b.storage[i] & mask; - let w = op(w0, w1) & mask; - if w0 != w unchecked { - changed = true; - self.storage[i] = w; - } - true +impl BigBitv { + + #[inline(always)] + fn process(b: &BigBitv, nbits: uint, op: fn(uint, uint) -> uint) -> bool { + let len = b.storage.len(); + assert (self.storage.len() == len); + let mut changed = false; + do uint::range(0, len) |i| { + let mask = big_mask(nbits, i); + let w0 = self.storage[i] & mask; + let w1 = b.storage[i] & mask; + let w = op(w0, w1) & mask; + if w0 != w unchecked { + changed = true; + self.storage[i] = w; } - changed + true } + changed } + #[inline(always)] fn each_storage(op: fn(&uint) -> bool) { for uint::range(0, self.storage.len()) |i| { @@ -125,20 +145,25 @@ struct BigBitv { if !b { break; } } } + #[inline(always)] fn invert() { for self.each_storage() |w| { w = !w } } + #[inline(always)] fn union(b: &BigBitv, nbits: uint) -> bool { self.process(b, nbits, lor) } + #[inline(always)] fn intersect(b: &BigBitv, nbits: uint) -> bool { self.process(b, nbits, land) } + #[inline(always)] fn become(b: &BigBitv, nbits: uint) -> bool { self.process(b, nbits, right) } + #[inline(always)] fn difference(b: &BigBitv, nbits: uint) -> bool { self.invert(); @@ -146,6 +171,7 @@ struct BigBitv { self.invert(); b } + #[inline(always)] pure fn get(i: uint) -> bool { let w = i / uint_bits; @@ -153,6 +179,7 @@ struct BigBitv { let x = 1 & self.storage[w] >> b; x == 1 } + #[inline(always)] fn set(i: uint, x: bool) { let w = i / uint_bits; @@ -161,6 +188,7 @@ struct BigBitv { self.storage[w] = if x { self.storage[w] | flag } else { self.storage[w] & !flag }; } + #[inline(always)] fn equals(b: &BigBitv, nbits: uint) -> bool { let len = b.storage.len(); @@ -171,6 +199,7 @@ struct BigBitv { } } } + } enum BitvVariant { Big(~BigBitv), Small(~SmallBitv) } @@ -179,80 +208,85 @@ enum Op {Union, Intersect, Assign, Difference} // The bitvector type struct Bitv { - let rep: BitvVariant; - let nbits: uint; + rep: BitvVariant, + nbits: uint +} - new(nbits: uint, init: bool) { - self.nbits = nbits; - if nbits <= 32 { - self.rep = Small(~SmallBitv(if init {!0} else {0})); - } - else { - let nelems = nbits/uint_bits + - if nbits % uint_bits == 0 {0} else {1}; - let elem = if init {!0} else {0}; - let s = to_mut(from_elem(nelems, elem)); - self.rep = Big(~BigBitv(s)); - }; - } - - priv { - fn die() -> ! { - fail ~"Tried to do operation on bit vectors with \ - different sizes"; +fn Bitv (nbits: uint, init: bool) -> Bitv { + let rep = if nbits <= 32 { + Small(~SmallBitv(if init {!0} else {0})) + } + else { + let nelems = nbits/uint_bits + + if nbits % uint_bits == 0 {0} else {1}; + let elem = if init {!0} else {0}; + let s = to_mut(from_elem(nelems, elem)); + Big(~BigBitv(s)) + }; + Bitv {rep: rep, nbits: nbits} +} + +priv impl Bitv { + + fn die() -> ! { + fail ~"Tried to do operation on bit vectors with different sizes"; + } + + #[inline(always)] + fn do_op(op: Op, other: &Bitv) -> bool { + if self.nbits != other.nbits { + self.die(); } - #[inline(always)] - fn do_op(op: Op, other: &Bitv) -> bool { - if self.nbits != other.nbits { - self.die(); - } - match self.rep { - Small(s) => match other.rep { - Small(s1) => match op { - Union => s.union(s1, self.nbits), - Intersect => s.intersect(s1, self.nbits), - Assign => s.become(s1, self.nbits), - Difference => s.difference(s1, self.nbits) - }, - Big(_) => self.die() - }, - Big(s) => match other.rep { - Small(_) => self.die(), - Big(s1) => match op { - Union => s.union(s1, self.nbits), - Intersect => s.intersect(s1, self.nbits), - Assign => s.become(s1, self.nbits), - Difference => s.difference(s1, self.nbits) - } - } + match self.rep { + Small(s) => match other.rep { + Small(s1) => match op { + Union => s.union(s1, self.nbits), + Intersect => s.intersect(s1, self.nbits), + Assign => s.become(s1, self.nbits), + Difference => s.difference(s1, self.nbits) + }, + Big(_) => self.die() + }, + Big(s) => match other.rep { + Small(_) => self.die(), + Big(s1) => match op { + Union => s.union(s1, self.nbits), + Intersect => s.intersect(s1, self.nbits), + Assign => s.become(s1, self.nbits), + Difference => s.difference(s1, self.nbits) } + } } } -/** - * Calculates the union of two bitvectors - * - * Sets `self` to the union of `self` and `v1`. Both bitvectors must be - * the same length. Returns 'true' if `self` changed. -*/ +} + +impl Bitv { + + /** + * Calculates the union of two bitvectors + * + * Sets `self` to the union of `self` and `v1`. Both bitvectors must be + * the same length. Returns 'true' if `self` changed. + */ #[inline(always)] fn union(v1: &Bitv) -> bool { self.do_op(Union, v1) } -/** - * Calculates the intersection of two bitvectors - * - * Sets `self` to the intersection of `self` and `v1`. Both bitvectors must be - * the same length. Returns 'true' if `self` changed. -*/ + /** + * Calculates the intersection of two bitvectors + * + * Sets `self` to the intersection of `self` and `v1`. Both bitvectors + * must be the same length. Returns 'true' if `self` changed. + */ #[inline(always)] fn intersect(v1: &Bitv) -> bool { self.do_op(Intersect, v1) } -/** - * Assigns the value of `v1` to `self` - * - * Both bitvectors must be the same length. Returns `true` if `self` was - * changed - */ + /** + * Assigns the value of `v1` to `self` + * + * Both bitvectors must be the same length. Returns `true` if `self` was + * changed + */ #[inline(always)] fn assign(v: &Bitv) -> bool { self.do_op(Assign, v) } @@ -282,11 +316,11 @@ struct Bitv { } } -/** - * Set the value of a bit at a given index - * - * `i` must be less than the length of the bitvector. - */ + /** + * Set the value of a bit at a given index + * + * `i` must be less than the length of the bitvector. + */ #[inline(always)] fn set(i: uint, x: bool) { assert (i < self.nbits); @@ -296,12 +330,12 @@ struct Bitv { } } -/** - * Compares two bitvectors - * - * Both bitvectors must be the same length. Returns `true` if both bitvectors - * contain identical elements. - */ + /** + * Compares two bitvectors + * + * Both bitvectors must be the same length. Returns `true` if both + * bitvectors contain identical elements. + */ #[inline(always)] fn equal(v1: Bitv) -> bool { if self.nbits != v1.nbits { return false; } @@ -342,18 +376,19 @@ struct Bitv { Big(s) => for s.each_storage() |w| { w = !w } } } -/** - * Calculate the difference between two bitvectors - * - * Sets each element of `v0` to the value of that element minus the element - * of `v1` at the same index. Both bitvectors must be the same length. - * - * Returns `true` if `v0` was changed. - */ - #[inline(always)] + /** + * Calculate the difference between two bitvectors + * + * Sets each element of `v0` to the value of that element minus the + * element of `v1` at the same index. Both bitvectors must be the same + * length. + * + * Returns `true` if `v0` was changed. + */ + #[inline(always)] fn difference(v: ~Bitv) -> bool { self.do_op(Difference, v) } - /// Returns true if all bits are 1 + /// Returns true if all bits are 1 #[inline(always)] fn is_true() -> bool { match self.rep { @@ -375,7 +410,6 @@ struct Bitv { } /// Returns true if all bits are 0 - fn is_false() -> bool { match self.rep { Small(b) => b.is_false(self.nbits), @@ -390,11 +424,11 @@ struct Bitv { return if self.get(i) { 1 } else { 0 }; } -/** - * Converts `self` to a vector of uint with the same length. - * - * Each uint in the resulting vector has either value 0u or 1u. - */ + /** + * Converts `self` to a vector of uint with the same length. + * + * Each uint in the resulting vector has either value 0u or 1u. + */ fn to_vec() -> ~[uint] { vec::from_fn(self.nbits, |x| self.init_to_vec(x)) } @@ -437,12 +471,12 @@ struct Bitv { vec::from_fn(self.nbits, |i| self[i]) } -/** - * Converts `self` to a string. - * - * The resulting string has the same length as `self`, and each - * character is either '0' or '1'. - */ + /** + * Converts `self` to a string. + * + * The resulting string has the same length as `self`, and each + * character is either '0' or '1'. + */ fn to_str() -> ~str { let mut rs = ~""; for self.each() |i| { if i { rs += ~"1"; } else { rs += ~"0"; } }; @@ -450,23 +484,23 @@ struct Bitv { } -/** - * Compare a bitvector to a vector of uint - * - * The uint vector is expected to only contain the values 0u and 1u. Both the - * bitvector and vector must have the same length - */ - fn eq_vec(v: ~[uint]) -> bool { - assert self.nbits == v.len(); - let mut i = 0; - while i < self.nbits { - let w0 = self.get(i); - let w1 = v[i]; - if !w0 && w1 != 0u || w0 && w1 == 0u { return false; } - i = i + 1; - } - true - } + /** + * Compare a bitvector to a vector of uint + * + * The uint vector is expected to only contain the values 0u and 1u. Both + * the bitvector and vector must have the same length + */ + fn eq_vec(v: ~[uint]) -> bool { + assert self.nbits == v.len(); + let mut i = 0; + while i < self.nbits { + let w0 = self.get(i); + let w1 = v[i]; + if !w0 && w1 != 0u || w0 && w1 == 0u { return false; } + i = i + 1; + } + true + } fn ones(f: fn(uint) -> bool) { for uint::range(0, self.nbits) |i| { @@ -476,7 +510,7 @@ struct Bitv { } } -} // end of bitv class +} /** * Transform a byte-vector into a bitv. Each byte becomes 8 bits, |
