Stabilize std::num

This commit stabilizes the `std::num` module:

* The `Int` and `Float` traits are deprecated in favor of (1) the
  newly-added inherent methods and (2) the generic traits available in
  rust-lang/num.

* The `Zero` and `One` traits are reintroduced in `std::num`, which
  together with various other traits allow you to recover the most
  common forms of generic programming.

* The `FromStrRadix` trait, and associated free function, is deprecated
  in favor of inherent implementations.

* A wide range of methods and constants for both integers and floating
  point numbers are now `#[stable]`, having been adjusted for integer
  guidelines.

* `is_positive` and `is_negative` are renamed to `is_sign_positive` and
  `is_sign_negative`, in order to address #22985

* The `Wrapping` type is moved to `std::num` and stabilized;
  `WrappingOps` is deprecated in favor of inherent methods on the
  integer types, and direct implementation of operations on
  `Wrapping<X>` for each concrete integer type `X`.

Closes #22985
Closes #21069

[breaking-change]

1 files changed, 3 insertions, 4 deletions

diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 532b632fac8..bcb265af926 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -20,7 +20,6 @@ use std::borrow::{IntoCow, Cow};
 use std::char;
 use std::fmt;
 use std::mem::replace;
-use std::num;
 use std::rc::Rc;
 
 pub use ext::tt::transcribe::{TtReader, new_tt_reader, new_tt_reader_with_doc_flag};
@@ -622,8 +621,8 @@ impl<'a> StringReader<'a> {
 
         // find the integer representing the name
         self.scan_digits(base);
-        let encoded_name : u32 = self.with_str_from(start_bpos, |s| {
-            num::from_str_radix(s, 10).unwrap_or_else(|_| {
+        let encoded_name: u32 = self.with_str_from(start_bpos, |s| {
+            u32::from_str_radix(s, 10).unwrap_or_else(|_| {
                 panic!("expected digits representing a name, got {:?}, {}, range [{:?},{:?}]",
                       s, whence, start_bpos, self.last_pos);
             })
@@ -641,7 +640,7 @@ impl<'a> StringReader<'a> {
         let start_bpos = self.last_pos;
         self.scan_digits(base);
         let encoded_ctxt : ast::SyntaxContext = self.with_str_from(start_bpos, |s| {
-            num::from_str_radix(s, 10).unwrap_or_else(|_| {
+            u32::from_str_radix(s, 10).unwrap_or_else(|_| {
                 panic!("expected digits representing a ctxt, got {:?}, {}", s, whence);
             })
         });