auto merge of #18827 : bjz/rust/rfc369-numerics, r=alexcrichton

This implements a considerable portion of rust-lang/rfcs#369 (tracked in #18640). Some interpretations had to be made in order to get this to work. The breaking changes are listed below:

[breaking-change]

- `core::num::{Num, Unsigned, Primitive}` have been deprecated and their re-exports removed from the `{std, core}::prelude`.
- `core::num::{Zero, One, Bounded}` have been deprecated. Use the static methods on `core::num::{Float, Int}` instead. There is no equivalent to `Zero::is_zero`. Use `(==)` with `{Float, Int}::zero` instead.
- `Signed::abs_sub` has been moved to `std::num::FloatMath`, and is no longer implemented for signed integers.
- `core::num::Signed` has been removed, and its methods have been moved to `core::num::Float` and a new trait, `core::num::SignedInt`. The methods now take the `self` parameter by value.
- `core::num::{Saturating, CheckedAdd, CheckedSub, CheckedMul, CheckedDiv}` have been removed, and their methods moved to `core::num::Int`. Their parameters are now taken by value. This means that
- `std::time::Duration` no longer implements `core::num::{Zero, CheckedAdd, CheckedSub}` instead defining the required methods non-polymorphically.
- `core::num::{zero, one, abs, signum}` have been deprecated. Use their respective methods instead.
- The `core::num::{next_power_of_two, is_power_of_two, checked_next_power_of_two}` functions have been deprecated in favor of methods defined a new trait, `core::num::UnsignedInt`
- `core::iter::{AdditiveIterator, MultiplicativeIterator}` are now only implemented for the built-in numeric types.
- `core::iter::{range, range_inclusive, range_step, range_step_inclusive}` now require `core::num::Int` to be implemented for the type they a re parametrized over.

Author: bors

src/doc/guide-lifetimes.md

@@ -51,6 +51,7 @@ expensive. So we'd like to define a function that takes the points just as
 a reference.
 
 ~~~
+# use std::num::Float;
 # struct Point {x: f64, y: f64}
 # fn sqrt(f: f64) -> f64 { 0.0 }
 fn compute_distance(p1: &Point, p2: &Point) -> f64 {

src/doc/guide-tasks.md

@@ -225,6 +225,7 @@ Here is another example showing how futures allow you to background
 computations. The workload will be distributed on the available cores.
 
 ```{rust}
+# use std::num::Float;
 # use std::sync::Future;
 fn partial_sum(start: uint) -> f64 {
     let mut local_sum = 0f64;
@@ -262,6 +263,7 @@ several computations on a single large vector of floats. Each task needs the
 full vector to perform its duty.
 
 ```{rust}
+use std::num::Float;
 use std::rand;
 use std::sync::Arc;
 

src/etc/vim/syntax/rust.vim

@@ -97,8 +97,7 @@ syn keyword rustTrait FromIterator IntoIterator Extend ExactSize
 syn keyword rustTrait Iterator DoubleEndedIterator
 syn keyword rustTrait RandomAccessIterator CloneableIterator
 syn keyword rustTrait OrdIterator MutableDoubleEndedIterator
-syn keyword rustTrait Num NumCast CheckedAdd CheckedSub CheckedMul CheckedDiv
-syn keyword rustTrait Signed Unsigned Primitive Int Float
+syn keyword rustTrait NumCast Int SignedInt UnsignedInt Float
 syn keyword rustTrait FloatMath ToPrimitive FromPrimitive
 syn keyword rustTrait Box
 syn keyword rustTrait GenericPath Path PosixPath WindowsPath

src/libarena/lib.rs

@@ -38,7 +38,7 @@ use std::cmp;
 use std::intrinsics::{TyDesc, get_tydesc};
 use std::intrinsics;
 use std::mem;
-use std::num;
+use std::num::{Int, UnsignedInt};
 use std::ptr;
 use std::rc::Rc;
 use std::rt::heap::{allocate, deallocate};
@@ -132,7 +132,7 @@ impl Drop for Arena {
 
 #[inline]
 fn round_up(base: uint, align: uint) -> uint {
-    (base.checked_add(&(align - 1))).unwrap() & !(align - 1)
+    (base.checked_add(align - 1)).unwrap() & !(align - 1)
 }
 
 // Walk down a chunk, running the destructors for any objects stored
@@ -187,7 +187,7 @@ impl Arena {
         self.chunks.borrow_mut().push(self.copy_head.borrow().clone());
 
         *self.copy_head.borrow_mut() =
-            chunk(num::next_power_of_two(new_min_chunk_size + 1u), true);
+            chunk((new_min_chunk_size + 1u).next_power_of_two(), true);
 
         return self.alloc_copy_inner(n_bytes, align);
     }
@@ -228,7 +228,7 @@ impl Arena {
         self.chunks.borrow_mut().push(self.head.borrow().clone());
 
         *self.head.borrow_mut() =
-            chunk(num::next_power_of_two(new_min_chunk_size + 1u), false);
+            chunk((new_min_chunk_size + 1u).next_power_of_two(), false);
 
         return self.alloc_noncopy_inner(n_bytes, align);
     }
@@ -376,8 +376,8 @@ fn calculate_size<T>(capacity: uint) -> uint {
     let mut size = mem::size_of::<TypedArenaChunk<T>>();
     size = round_up(size, mem::min_align_of::<T>());
     let elem_size = mem::size_of::<T>();
-    let elems_size = elem_size.checked_mul(&capacity).unwrap();
-    size = size.checked_add(&elems_size).unwrap();
+    let elems_size = elem_size.checked_mul(capacity).unwrap();
+    size = size.checked_add(elems_size).unwrap();
     size
 }
 
@@ -432,7 +432,7 @@ impl<T> TypedArenaChunk<T> {
     #[inline]
     fn end(&self) -> *const u8 {
         unsafe {
-            let size = mem::size_of::<T>().checked_mul(&self.capacity).unwrap();
+            let size = mem::size_of::<T>().checked_mul(self.capacity).unwrap();
             self.start().offset(size as int)
         }
     }
@@ -481,7 +481,7 @@ impl<T> TypedArena<T> {
     fn grow(&self) {
         unsafe {
             let chunk = *self.first.borrow_mut();
-            let new_capacity = (*chunk).capacity.checked_mul(&2).unwrap();
+            let new_capacity = (*chunk).capacity.checked_mul(2).unwrap();
             let chunk = TypedArenaChunk::<T>::new(chunk, new_capacity);
             self.ptr.set((*chunk).start() as *const T);
             self.end.set((*chunk).end() as *const T);

src/libcollections/bit.rs

@@ -22,6 +22,7 @@
 //!
 //! ```
 //! use std::collections::{BitvSet, Bitv};
+//! use std::num::Float;
 //! use std::iter;
 //!
 //! let max_prime = 10000;
@@ -69,6 +70,7 @@ use core::default::Default;
 use core::fmt;
 use core::iter::{Chain, Enumerate, Repeat, Skip, Take};
 use core::iter;
+use core::num::Int;
 use core::slice;
 use core::u32;
 use std::hash;

src/libcollections/enum_set.rs

@@ -15,6 +15,7 @@
 
 use core::prelude::*;
 use core::fmt;
+use core::num::Int;
 
 // FIXME(contentions): implement union family of methods? (general design may be wrong here)
 

src/libcollections/hash/mod.rs

@@ -69,6 +69,7 @@ use alloc::boxed::Box;
 use alloc::rc::Rc;
 use core::intrinsics::TypeId;
 use core::mem;
+use core::num::Int;
 
 use vec::Vec;
 

src/libcollections/vec.rs

@@ -21,7 +21,7 @@ use core::default::Default;
 use core::fmt;
 use core::kinds::marker::{ContravariantLifetime, InvariantType};
 use core::mem;
-use core::num;
+use core::num::{Int, UnsignedInt};
 use core::ops;
 use core::ptr;
 use core::raw::Slice as RawSlice;
@@ -161,7 +161,7 @@ impl<T> Vec<T> {
         } else if capacity == 0 {
             Vec::new()
         } else {
-            let size = capacity.checked_mul(&mem::size_of::<T>())
+            let size = capacity.checked_mul(mem::size_of::<T>())
                                .expect("capacity overflow");
             let ptr = unsafe { allocate(size, mem::min_align_of::<T>()) };
             Vec { ptr: ptr as *mut T, len: 0, cap: capacity }
@@ -587,11 +587,11 @@ impl<T> Vec<T> {
     #[unstable = "matches collection reform specification, waiting for dust to settle"]
     pub fn reserve(&mut self, additional: uint) {
         if self.cap - self.len < additional {
-            match self.len.checked_add(&additional) {
+            match self.len.checked_add(additional) {
                 None => panic!("Vec::reserve: `uint` overflow"),
                 // if the checked_add
                 Some(new_cap) => {
-                    let amort_cap = num::next_power_of_two(new_cap);
+                    let amort_cap = new_cap.next_power_of_two();
                     // next_power_of_two will overflow to exactly 0 for really big capacities
                     if amort_cap == 0 {
                         self.grow_capacity(new_cap);
@@ -624,7 +624,7 @@ impl<T> Vec<T> {
     #[unstable = "matches collection reform specification, waiting for dust to settle"]
     pub fn reserve_exact(&mut self, additional: uint) {
         if self.cap - self.len < additional {
-            match self.len.checked_add(&additional) {
+            match self.len.checked_add(additional) {
                 None => panic!("Vec::reserve: `uint` overflow"),
                 Some(new_cap) => self.grow_capacity(new_cap)
             }
@@ -957,7 +957,7 @@ impl<T> Vec<T> {
     pub fn push(&mut self, value: T) {
         if mem::size_of::<T>() == 0 {
             // zero-size types consume no memory, so we can't rely on the address space running out
-            self.len = self.len.checked_add(&1).expect("length overflow");
+            self.len = self.len.checked_add(1).expect("length overflow");
             unsafe { mem::forget(value); }
             return
         }
@@ -1050,7 +1050,7 @@ impl<T> Vec<T> {
         if mem::size_of::<T>() == 0 { return }
 
         if capacity > self.cap {
-            let size = capacity.checked_mul(&mem::size_of::<T>())
+            let size = capacity.checked_mul(mem::size_of::<T>())
                                .expect("capacity overflow");
             unsafe {
                 self.ptr = alloc_or_realloc(self.ptr, self.cap * mem::size_of::<T>(), size);

src/libcore/cmp.rs

@@ -19,6 +19,8 @@
 //! operators, you could do the following:
 //!
 //! ```rust
+//! use core::num::SignedInt;
+//!
 //! // Our type.
 //! struct SketchyNum {
 //!     num : int

src/libcore/fmt/float.rs

@@ -13,8 +13,8 @@
 use char;
 use fmt;
 use iter::{range, DoubleEndedIterator};
-use num::{Float, FPNaN, FPInfinite, ToPrimitive, Primitive};
-use num::{Zero, One, cast};
+use num::{Float, FPNaN, FPInfinite, ToPrimitive};
+use num::cast;
 use result::Ok;
 use slice::{mod, SlicePrelude};
 use str::StrPrelude;
@@ -79,7 +79,7 @@ static DIGIT_E_RADIX: uint = ('e' as uint) - ('a' as uint) + 11u;
  * - Fails if `radix` > 25 and `exp_format` is `ExpBin` due to conflict
  *   between digit and exponent sign `'p'`.
  */
-pub fn float_to_str_bytes_common<T: Primitive + Float, U>(
+pub fn float_to_str_bytes_common<T: Float, U>(
     num: T,
     radix: uint,
     negative_zero: bool,
@@ -97,8 +97,8 @@ pub fn float_to_str_bytes_common<T: Primitive + Float, U>(
         _ => ()
     }
 
-    let _0: T = Zero::zero();
-    let _1: T = One::one();
+    let _0: T = Float::zero();
+    let _1: T = Float::one();
 
     match num.classify() {
         FPNaN => return f("NaN".as_bytes()),

src/libcore/fmt/mod.rs

@@ -620,7 +620,7 @@ impl<'a, T> Pointer for &'a mut T {
 macro_rules! floating(($ty:ident) => {
     impl Float for $ty {
         fn fmt(&self, fmt: &mut Formatter) -> Result {
-            use num::{Float, Signed};
+            use num::Float;
 
             let digits = match fmt.precision {
                 Some(i) => float::DigExact(i),
@@ -641,7 +641,7 @@ macro_rules! floating(($ty:ident) => {
 
     impl LowerExp for $ty {
         fn fmt(&self, fmt: &mut Formatter) -> Result {
-            use num::{Float, Signed};
+            use num::Float;
 
             let digits = match fmt.precision {
                 Some(i) => float::DigExact(i),
@@ -662,7 +662,7 @@ macro_rules! floating(($ty:ident) => {
 
     impl UpperExp for $ty {
         fn fmt(&self, fmt: &mut Formatter) -> Result {
-            use num::{Float, Signed};
+            use num::Float;
 
             let digits = match fmt.precision {
                 Some(i) => float::DigExact(i),

src/libcore/fmt/num.rs

@@ -16,7 +16,7 @@
 
 use fmt;
 use iter::DoubleEndedIterator;
-use num::{Int, cast, zero};
+use num::{Int, cast};
 use slice::SlicePrelude;
 
 /// A type that represents a specific radix
@@ -35,10 +35,11 @@ trait GenericRadix {
     fn fmt_int<T: Int>(&self, mut x: T, f: &mut fmt::Formatter) -> fmt::Result {
         // The radix can be as low as 2, so we need a buffer of at least 64
         // characters for a base 2 number.
+        let zero = Int::zero();
+        let is_positive = x >= zero;
         let mut buf = [0u8, ..64];
-        let base = cast(self.base()).unwrap();
         let mut curr = buf.len();
-        let is_positive = x >= zero();
+        let base = cast(self.base()).unwrap();
         if is_positive {
             // Accumulate each digit of the number from the least significant
             // to the most significant figure.
@@ -47,16 +48,16 @@ trait GenericRadix {
                 x = x / base;                             // Deaccumulate the number.
                 *byte = self.digit(cast(n).unwrap());     // Store the digit in the buffer.
                 curr -= 1;
-                if x == zero() { break; }                 // No more digits left to accumulate.
+                if x == zero { break };                   // No more digits left to accumulate.
             }
         } else {
             // Do the same as above, but accounting for two's complement.
             for byte in buf.iter_mut().rev() {
-                let n = -(x % base);                      // Get the current place value.
+                let n = zero - (x % base);                // Get the current place value.
                 x = x / base;                             // Deaccumulate the number.
                 *byte = self.digit(cast(n).unwrap());     // Store the digit in the buffer.
                 curr -= 1;
-                if x == zero() { break; }                 // No more digits left to accumulate.
+                if x == zero { break };                   // No more digits left to accumulate.
             }
         }
         f.pad_integral(is_positive, self.prefix(), buf[curr..])