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Convert vec::{bsearch, bsearch_elem} to methods.
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huonw committed Jun 30, 2013
1 parent 562dea1 commit faa8f8f
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Showing 4 changed files with 95 additions and 86 deletions.
4 changes: 2 additions & 2 deletions src/etc/unicode.py
Original file line number Diff line number Diff line change
Expand Up @@ -124,9 +124,9 @@ def emit_bsearch_range_table(f):
f.write("""
fn bsearch_range_table(c: char, r: &'static [(char,char)]) -> bool {
use cmp::{Equal, Less, Greater};
use vec::bsearch;
use vec::ImmutableVector;
use option::None;
(do bsearch(r) |&(lo,hi)| {
(do r.bsearch |&(lo,hi)| {
if lo <= c && c <= hi { Equal }
else if hi < c { Less }
else { Greater }
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2 changes: 1 addition & 1 deletion src/libstd/prelude.rs
Original file line number Diff line number Diff line change
Expand Up @@ -73,7 +73,7 @@ pub use tuple::{ImmutableTuple2, ImmutableTuple3, ImmutableTuple4, ImmutableTupl
pub use tuple::{ImmutableTuple6, ImmutableTuple7, ImmutableTuple8, ImmutableTuple9};
pub use tuple::{ImmutableTuple10, ImmutableTuple11, ImmutableTuple12};
pub use vec::{VectorVector, CopyableVector, ImmutableVector};
pub use vec::{ImmutableEqVector, ImmutableCopyableVector};
pub use vec::{ImmutableEqVector, ImmutableTotalOrdVector, ImmutableCopyableVector};
pub use vec::{OwnedVector, OwnedCopyableVector, MutableVector};
pub use io::{Reader, ReaderUtil, Writer, WriterUtil};

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8 changes: 4 additions & 4 deletions src/libstd/unicode.rs
Original file line number Diff line number Diff line change
Expand Up @@ -16,9 +16,9 @@ pub mod general_category {

fn bsearch_range_table(c: char, r: &'static [(char,char)]) -> bool {
use cmp::{Equal, Less, Greater};
use vec::bsearch;
use vec::ImmutableVector;
use option::None;
(do bsearch(r) |&(lo,hi)| {
(do r.bsearch |&(lo,hi)| {
if lo <= c && c <= hi { Equal }
else if hi < c { Less }
else { Greater }
Expand Down Expand Up @@ -1451,9 +1451,9 @@ pub mod derived_property {

fn bsearch_range_table(c: char, r: &'static [(char,char)]) -> bool {
use cmp::{Equal, Less, Greater};
use vec::bsearch;
use vec::ImmutableVector;
use option::None;
(do bsearch(r) |&(lo,hi)| {
(do r.bsearch |&(lo,hi)| {
if lo <= c && c <= hi { Equal }
else if hi < c { Less }
else { Greater }
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167 changes: 88 additions & 79 deletions src/libstd/vec.rs
Original file line number Diff line number Diff line change
Expand Up @@ -646,44 +646,6 @@ impl<'self, T:Copy> VectorVector<T> for &'self [&'self [T]] {
}
}

/**
* Binary search a sorted vector with a comparator function.
*
* The comparator should implement an order consistent with the sort
* order of the underlying vector, returning an order code that indicates
* whether its argument is `Less`, `Equal` or `Greater` the desired target.
*
* Returns the index where the comparator returned `Equal`, or `None` if
* not found.
*/
pub fn bsearch<T>(v: &[T], f: &fn(&T) -> Ordering) -> Option<uint> {
let mut base : uint = 0;
let mut lim : uint = v.len();

while lim != 0 {
let ix = base + (lim >> 1);
match f(&v[ix]) {
Equal => return Some(ix),
Less => {
base = ix + 1;
lim -= 1;
}
Greater => ()
}
lim >>= 1;
}
return None;
}

/**
* Binary search a sorted vector for a given element.
*
* Returns the index of the element or None if not found.
*/
pub fn bsearch_elem<T:TotalOrd>(v: &[T], x: &T) -> Option<uint> {
bsearch(v, |p| p.cmp(x))
}

// FIXME: if issue #586 gets implemented, could have a postcondition
// saying the two result lists have the same length -- or, could
// return a nominal record with a constraint saying that, instead of
Expand Down Expand Up @@ -1119,6 +1081,8 @@ pub trait ImmutableVector<'self, T> {
fn flat_map<U>(&self, f: &fn(t: &T) -> ~[U]) -> ~[U];
fn filter_mapped<U:Copy>(&self, f: &fn(t: &T) -> Option<U>) -> ~[U];
unsafe fn unsafe_ref(&self, index: uint) -> *T;

fn bsearch(&self, f: &fn(&T) -> Ordering) -> Option<uint>;
}

/// Extension methods for vectors
Expand Down Expand Up @@ -1264,6 +1228,35 @@ impl<'self,T> ImmutableVector<'self, T> for &'self [T] {
let (ptr, _): (*T, uint) = transmute(*self);
ptr.offset(index)
}

/**
* Binary search a sorted vector with a comparator function.
*
* The comparator should implement an order consistent with the sort
* order of the underlying vector, returning an order code that indicates
* whether its argument is `Less`, `Equal` or `Greater` the desired target.
*
* Returns the index where the comparator returned `Equal`, or `None` if
* not found.
*/
fn bsearch(&self, f: &fn(&T) -> Ordering) -> Option<uint> {
let mut base : uint = 0;
let mut lim : uint = self.len();

while lim != 0 {
let ix = base + (lim >> 1);
match f(&self[ix]) {
Equal => return Some(ix),
Less => {
base = ix + 1;
lim -= 1;
}
Greater => ()
}
lim >>= 1;
}
return None;
}
}

#[allow(missing_doc)]
Expand Down Expand Up @@ -1293,6 +1286,22 @@ impl<'self,T:Eq> ImmutableEqVector<T> for &'self [T] {
}
}

#[allow(missing_doc)]
pub trait ImmutableTotalOrdVector<T: TotalOrd> {
fn bsearch_elem(&self, x: &T) -> Option<uint>;
}

impl<'self, T: TotalOrd> ImmutableTotalOrdVector<T> for &'self [T] {
/**
* Binary search a sorted vector for a given element.
*
* Returns the index of the element or None if not found.
*/
fn bsearch_elem(&self, x: &T) -> Option<uint> {
self.bsearch(|p| p.cmp(x))
}
}

#[allow(missing_doc)]
pub trait ImmutableCopyableVector<T> {
fn filtered(&self, f: &fn(&T) -> bool) -> ~[T];
Expand Down Expand Up @@ -2841,47 +2850,47 @@ mod tests {

#[test]
fn test_bsearch_elem() {
assert_eq!(bsearch_elem([1,2,3,4,5], &5), Some(4));
assert_eq!(bsearch_elem([1,2,3,4,5], &4), Some(3));
assert_eq!(bsearch_elem([1,2,3,4,5], &3), Some(2));
assert_eq!(bsearch_elem([1,2,3,4,5], &2), Some(1));
assert_eq!(bsearch_elem([1,2,3,4,5], &1), Some(0));

assert_eq!(bsearch_elem([2,4,6,8,10], &1), None);
assert_eq!(bsearch_elem([2,4,6,8,10], &5), None);
assert_eq!(bsearch_elem([2,4,6,8,10], &4), Some(1));
assert_eq!(bsearch_elem([2,4,6,8,10], &10), Some(4));

assert_eq!(bsearch_elem([2,4,6,8], &1), None);
assert_eq!(bsearch_elem([2,4,6,8], &5), None);
assert_eq!(bsearch_elem([2,4,6,8], &4), Some(1));
assert_eq!(bsearch_elem([2,4,6,8], &8), Some(3));

assert_eq!(bsearch_elem([2,4,6], &1), None);
assert_eq!(bsearch_elem([2,4,6], &5), None);
assert_eq!(bsearch_elem([2,4,6], &4), Some(1));
assert_eq!(bsearch_elem([2,4,6], &6), Some(2));

assert_eq!(bsearch_elem([2,4], &1), None);
assert_eq!(bsearch_elem([2,4], &5), None);
assert_eq!(bsearch_elem([2,4], &2), Some(0));
assert_eq!(bsearch_elem([2,4], &4), Some(1));

assert_eq!(bsearch_elem([2], &1), None);
assert_eq!(bsearch_elem([2], &5), None);
assert_eq!(bsearch_elem([2], &2), Some(0));

assert_eq!(bsearch_elem([], &1), None);
assert_eq!(bsearch_elem([], &5), None);

assert!(bsearch_elem([1,1,1,1,1], &1) != None);
assert!(bsearch_elem([1,1,1,1,2], &1) != None);
assert!(bsearch_elem([1,1,1,2,2], &1) != None);
assert!(bsearch_elem([1,1,2,2,2], &1) != None);
assert_eq!(bsearch_elem([1,2,2,2,2], &1), Some(0));

assert_eq!(bsearch_elem([1,2,3,4,5], &6), None);
assert_eq!(bsearch_elem([1,2,3,4,5], &0), None);
assert_eq!([1,2,3,4,5].bsearch_elem(&5), Some(4));
assert_eq!([1,2,3,4,5].bsearch_elem(&4), Some(3));
assert_eq!([1,2,3,4,5].bsearch_elem(&3), Some(2));
assert_eq!([1,2,3,4,5].bsearch_elem(&2), Some(1));
assert_eq!([1,2,3,4,5].bsearch_elem(&1), Some(0));

assert_eq!([2,4,6,8,10].bsearch_elem(&1), None);
assert_eq!([2,4,6,8,10].bsearch_elem(&5), None);
assert_eq!([2,4,6,8,10].bsearch_elem(&4), Some(1));
assert_eq!([2,4,6,8,10].bsearch_elem(&10), Some(4));

assert_eq!([2,4,6,8].bsearch_elem(&1), None);
assert_eq!([2,4,6,8].bsearch_elem(&5), None);
assert_eq!([2,4,6,8].bsearch_elem(&4), Some(1));
assert_eq!([2,4,6,8].bsearch_elem(&8), Some(3));

assert_eq!([2,4,6].bsearch_elem(&1), None);
assert_eq!([2,4,6].bsearch_elem(&5), None);
assert_eq!([2,4,6].bsearch_elem(&4), Some(1));
assert_eq!([2,4,6].bsearch_elem(&6), Some(2));

assert_eq!([2,4].bsearch_elem(&1), None);
assert_eq!([2,4].bsearch_elem(&5), None);
assert_eq!([2,4].bsearch_elem(&2), Some(0));
assert_eq!([2,4].bsearch_elem(&4), Some(1));

assert_eq!([2].bsearch_elem(&1), None);
assert_eq!([2].bsearch_elem(&5), None);
assert_eq!([2].bsearch_elem(&2), Some(0));

assert_eq!([].bsearch_elem(&1), None);
assert_eq!([].bsearch_elem(&5), None);

assert!([1,1,1,1,1].bsearch_elem(&1) != None);
assert!([1,1,1,1,2].bsearch_elem(&1) != None);
assert!([1,1,1,2,2].bsearch_elem(&1) != None);
assert!([1,1,2,2,2].bsearch_elem(&1) != None);
assert_eq!([1,2,2,2,2].bsearch_elem(&1), Some(0));

assert_eq!([1,2,3,4,5].bsearch_elem(&6), None);
assert_eq!([1,2,3,4,5].bsearch_elem(&0), None);
}

#[test]
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