std: Remove deprecated/unstable num functionality

This commit removes all the old casting/generic traits from `std::num` that are
no longer in use by the standard library. This additionally removes the old
`strconv` module which has not seen much use in quite a long time. All generic
functionality has been supplanted with traits in the `num` crate and the
`strconv` module is supplanted with the [rust-strconv crate][rust-strconv].

[rust-strconv]: https://github.com/lifthrasiir/rust-strconv

This is a breaking change due to the removal of these deprecated crates, and the
alternative crates are listed above.

[breaking-change]

Author: alexcrichton

src/libcollections/string.rs

@@ -1060,14 +1060,6 @@ impl<'a> IntoCow<'a, str> for &'a str {
     }
 }
 
-#[allow(deprecated)]
-impl<'a> Str for Cow<'a, str> {
-    #[inline]
-    fn as_slice<'b>(&'b self) -> &'b str {
-        &**self
-    }
-}
-
 #[stable(feature = "rust1", since = "1.0.0")]
 impl fmt::Write for String {
     #[inline]

src/libcore/fmt/float.rs

@@ -11,15 +11,15 @@
 pub use self::ExponentFormat::*;
 pub use self::SignificantDigits::*;
 
-use char::{self, CharExt};
+use prelude::*;
+
+use char;
 use fmt;
-use iter::Iterator;
-use num::{cast, Float, ToPrimitive};
+use num::Float;
 use num::FpCategory as Fp;
-use ops::FnOnce;
-use result::Result::Ok;
-use slice::{self, SliceExt};
-use str::{self, StrExt};
+use ops::{Div, Rem, Mul};
+use slice;
+use str;
 
 /// A flag that specifies whether to use exponential (scientific) notation.
 pub enum ExponentFormat {
@@ -42,6 +42,21 @@ pub enum SignificantDigits {
     DigExact(usize)
 }
 
+#[doc(hidden)]
+pub trait MyFloat: Float + PartialEq + PartialOrd + Div<Output=Self> +
+                   Mul<Output=Self> + Rem<Output=Self> + Copy {
+    fn from_u32(u: u32) -> Self;
+    fn to_i32(&self) -> i32;
+}
+
+macro_rules! doit {
+    ($($t:ident)*) => ($(impl MyFloat for $t {
+        fn from_u32(u: u32) -> $t { u as $t }
+        fn to_i32(&self) -> i32 { *self as i32 }
+    })*)
+}
+doit! { f32 f64 }
+
 /// Converts a float number to its string representation.
 /// This is meant to be a common base implementation for various formatting styles.
 /// The number is assumed to be non-negative, callers use `Formatter::pad_integral`
@@ -63,7 +78,7 @@ pub enum SignificantDigits {
 /// # Panics
 ///
 /// - Panics if `num` is negative.
-pub fn float_to_str_bytes_common<T: Float, U, F>(
+pub fn float_to_str_bytes_common<T: MyFloat, U, F>(
     num: T,
     digits: SignificantDigits,
     exp_format: ExponentFormat,
@@ -72,10 +87,10 @@ pub fn float_to_str_bytes_common<T: Float, U, F>(
 ) -> U where
     F: FnOnce(&str) -> U,
 {
-    let _0: T = Float::zero();
-    let _1: T = Float::one();
+    let _0: T = T::zero();
+    let _1: T = T::one();
     let radix: u32 = 10;
-    let radix_f: T = cast(radix).unwrap();
+    let radix_f = T::from_u32(radix);
 
     assert!(num.is_nan() || num >= _0, "float_to_str_bytes_common: number is negative");
 
@@ -99,7 +114,7 @@ pub fn float_to_str_bytes_common<T: Float, U, F>(
     let (num, exp) = match exp_format {
         ExpDec if num != _0 => {
             let exp = num.log10().floor();
-            (num / radix_f.powf(exp), cast::<T, i32>(exp).unwrap())
+            (num / radix_f.powf(exp), exp.to_i32())
         }
         _ => (num, 0)
     };
@@ -114,7 +129,7 @@ pub fn float_to_str_bytes_common<T: Float, U, F>(
         deccum = deccum / radix_f;
         deccum = deccum.trunc();
 
-        let c = char::from_digit(current_digit.to_isize().unwrap() as u32, radix);
+        let c = char::from_digit(current_digit.to_i32() as u32, radix);
         buf[end] = c.unwrap() as u8;
         end += 1;
 
@@ -158,7 +173,7 @@ pub fn float_to_str_bytes_common<T: Float, U, F>(
 
             let current_digit = deccum.trunc();
 
-            let c = char::from_digit(current_digit.to_isize().unwrap() as u32, radix);
+            let c = char::from_digit(current_digit.to_i32() as u32, radix);
             buf[end] = c.unwrap() as u8;
             end += 1;
 

src/libcore/fmt/mod.rs

@@ -12,21 +12,16 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 
+use prelude::*;
+
 use cell::{Cell, RefCell, Ref, RefMut, BorrowState};
-use char::CharExt;
-use clone::Clone;
-use iter::Iterator;
-use marker::{Copy, PhantomData, Sized};
+use marker::PhantomData;
 use mem;
-use num::Float;
-use option::Option;
-use option::Option::{Some, None};
-use result::Result::Ok;
-use ops::{Deref, FnOnce};
+use ops::Deref;
 use result;
-use slice::SliceExt;
+use num::Float;
 use slice;
-use str::{self, StrExt};
+use str;
 use self::rt::v1::Alignment;
 
 pub use self::num::radix;
@@ -912,7 +907,8 @@ impl<'a, T> Pointer for &'a mut T {
 }
 
 // Common code of floating point Debug and Display.
-fn float_to_str_common<T: Float, F>(num: &T, precision: Option<usize>, post: F) -> Result
+fn float_to_str_common<T: float::MyFloat, F>(num: &T, precision: Option<usize>,
+                                             post: F) -> Result
         where F : FnOnce(&str) -> Result {
     let digits = match precision {
         Some(i) => float::DigExact(i),
@@ -950,8 +946,6 @@ macro_rules! floating { ($ty:ident) => {
     #[stable(feature = "rust1", since = "1.0.0")]
     impl LowerExp for $ty {
         fn fmt(&self, fmt: &mut Formatter) -> Result {
-            use num::Float;
-
             let digits = match fmt.precision {
                 Some(i) => float::DigExact(i),
                 None => float::DigMax(6),
@@ -969,8 +963,6 @@ macro_rules! floating { ($ty:ident) => {
     #[stable(feature = "rust1", since = "1.0.0")]
     impl UpperExp for $ty {
         fn fmt(&self, fmt: &mut Formatter) -> Result {
-            use num::Float;
-
             let digits = match fmt.precision {
                 Some(i) => float::DigExact(i),
                 None => float::DigMax(6),

src/libcore/fmt/num.rs

@@ -14,12 +14,28 @@
 
 #![allow(unsigned_negation)]
 
+use prelude::*;
+
 use fmt;
-use iter::Iterator;
-use num::{Int, cast};
-use slice::SliceExt;
+use num::Zero;
+use ops::{Div, Rem, Sub};
 use str;
 
+#[doc(hidden)]
+trait Int: Zero + PartialEq + PartialOrd + Div<Output=Self> + Rem<Output=Self> +
+           Sub<Output=Self> + Copy {
+    fn from_u8(u: u8) -> Self;
+    fn to_u8(&self) -> u8;
+}
+
+macro_rules! doit {
+    ($($t:ident)*) => ($(impl Int for $t {
+        fn from_u8(u: u8) -> $t { u as $t }
+        fn to_u8(&self) -> u8 { *self as u8 }
+    })*)
+}
+doit! { i8 i16 i32 i64 isize u8 u16 u32 u64 usize }
+
 /// A type that represents a specific radix
 #[doc(hidden)]
 trait GenericRadix {
@@ -33,33 +49,32 @@ trait GenericRadix {
     fn digit(&self, x: u8) -> u8;
 
     /// Format an integer using the radix using a formatter.
-    #[allow(deprecated)] // Int
     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 zero = T::zero();
         let is_positive = x >= zero;
         let mut buf = [0; 64];
         let mut curr = buf.len();
-        let base = cast(self.base()).unwrap();
+        let base = T::from_u8(self.base());
         if is_positive {
             // Accumulate each digit of the number from the least significant
             // to the most significant figure.
             for byte in buf.iter_mut().rev() {
-                let n = 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.
+                let n = x % base;              // Get the current place value.
+                x = x / base;                  // Deaccumulate the number.
+                *byte = self.digit(n.to_u8()); // 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 = 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.
+                let n = zero - (x % base);     // Get the current place value.
+                x = x / base;                  // Deaccumulate the number.
+                *byte = self.digit(n.to_u8()); // 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.
             }
         }
         let buf = unsafe { str::from_utf8_unchecked(&buf[curr..]) };

src/libcore/iter.rs

@@ -64,7 +64,7 @@ use cmp::{Ord, PartialOrd, PartialEq};
 use default::Default;
 use marker;
 use mem;
-use num::{Int, Zero, One};
+use num::{Zero, One};
 use ops::{self, Add, Sub, FnMut, Mul, RangeFrom};
 use option::Option::{self, Some, None};
 use marker::Sized;
@@ -2647,80 +2647,6 @@ impl<A: Step + Zero + Clone> Iterator for StepBy<A, ops::Range<A>> {
     }
 }
 
-/// An iterator over the range [start, stop] by `step`. It handles overflow by stopping.
-#[derive(Clone)]
-#[unstable(feature = "core",
-           reason = "likely to be replaced by range notation and adapters")]
-pub struct RangeStepInclusive<A> {
-    state: A,
-    stop: A,
-    step: A,
-    rev: bool,
-    done: bool,
-}
-
-/// Returns an iterator over the range [start, stop] by `step`.
-///
-/// It handles overflow by stopping.
-///
-/// # Examples
-///
-/// ```
-/// # #![feature(core)]
-/// use std::iter::range_step_inclusive;
-///
-/// for i in range_step_inclusive(0, 10, 2) {
-///     println!("{}", i);
-/// }
-/// ```
-///
-/// This prints:
-///
-/// ```text
-/// 0
-/// 2
-/// 4
-/// 6
-/// 8
-/// 10
-/// ```
-#[inline]
-#[unstable(feature = "core",
-           reason = "likely to be replaced by range notation and adapters")]
-#[allow(deprecated)]
-pub fn range_step_inclusive<A: Int>(start: A, stop: A, step: A) -> RangeStepInclusive<A> {
-    let rev = step < Int::zero();
-    RangeStepInclusive {
-        state: start,
-        stop: stop,
-        step: step,
-        rev: rev,
-        done: false,
-    }
-}
-
-#[unstable(feature = "core",
-           reason = "likely to be replaced by range notation and adapters")]
-#[allow(deprecated)]
-impl<A: Int> Iterator for RangeStepInclusive<A> {
-    type Item = A;
-
-    #[inline]
-    fn next(&mut self) -> Option<A> {
-        if !self.done && ((self.rev && self.state >= self.stop) ||
-                          (!self.rev && self.state <= self.stop)) {
-            let result = self.state;
-            match self.state.checked_add(self.step) {
-                Some(x) => self.state = x,
-                None => self.done = true
-            }
-            Some(result)
-        } else {
-            None
-        }
-    }
-}
-
 macro_rules! range_exact_iter_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]