auto merge of #19407 : frewsxcv/rust/rm-reexports, r=sfackler

In regards to:

#19253 (comment)

This commit:

* Changes the #deriving code so that it generates code that utilizes fewer
  reexports (in particur Option::\*, Result::\*, and Ordering::\*), which is necessary to
  remove those reexports in the future
* Changes other areas of the codebase so that fewer reexports are utilized

Author: bors

src/doc/reference.md

@@ -994,7 +994,7 @@ An example of `use` declarations:
 
 ```
 use std::iter::range_step;
-use std::option::{Some, None};
+use std::option::Option::{Some, None};
 use std::collections::hash_map::{mod, HashMap};
 
 fn foo<T>(_: T){}
@@ -1004,8 +1004,8 @@ fn main() {
     // Equivalent to 'std::iter::range_step(0u, 10u, 2u);'
     range_step(0u, 10u, 2u);
 
-    // Equivalent to 'foo(vec![std::option::Some(1.0f64),
-    // std::option::None]);'
+    // Equivalent to 'foo(vec![std::option::Option::Some(1.0f64),
+    // std::option::Option::None]);'
     foo(vec![Some(1.0f64), None]);
 
     // Both `hash_map` and `HashMap` are in scope.

src/etc/unicode.py

@@ -292,7 +292,7 @@ def escape_char(c):
 def emit_bsearch_range_table(f):
     f.write("""
 fn bsearch_range_table(c: char, r: &'static [(char,char)]) -> bool {
-    use core::cmp::{Equal, Less, Greater};
+    use core::cmp::Ordering::{Equal, Less, Greater};
     use core::slice::SlicePrelude;
     r.binary_search(|&(lo,hi)| {
         if lo <= c && c <= hi { Equal }
@@ -350,10 +350,11 @@ def emit_regex_module(f, cats, w_data):
 def emit_conversions_module(f, lowerupper, upperlower):
     f.write("pub mod conversions {")
     f.write("""
-    use core::cmp::{Equal, Less, Greater};
+    use core::cmp::Ordering::{Equal, Less, Greater};
     use core::slice::SlicePrelude;
     use core::tuple::Tuple2;
-    use core::option::{Option, Some, None};
+    use core::option::Option;
+    use core::option::Option::{Some, None};
     use core::slice;
 
     pub fn to_lower(c: char) -> char {
@@ -403,7 +404,7 @@ def emit_grapheme_module(f, grapheme_table, grapheme_cats):
     f.write("""    }
 
     fn bsearch_range_value_table(c: char, r: &'static [(char, char, GraphemeCat)]) -> GraphemeCat {
-        use core::cmp::{Equal, Less, Greater};
+        use core::cmp::Ordering::{Equal, Less, Greater};
         match r.binary_search(|&(lo, hi, _)| {
             if lo <= c && c <= hi { Equal }
             else if hi < c { Less }
@@ -430,12 +431,13 @@ def emit_grapheme_module(f, grapheme_table, grapheme_cats):
 
 def emit_charwidth_module(f, width_table):
     f.write("pub mod charwidth {\n")
-    f.write("    use core::option::{Option, Some, None};\n")
+    f.write("    use core::option::Option;\n")
+    f.write("    use core::option::Option::{Some, None};\n")
     f.write("    use core::slice::SlicePrelude;\n")
     f.write("    use core::slice;\n")
     f.write("""
     fn bsearch_range_value_table(c: char, is_cjk: bool, r: &'static [(char, char, u8, u8)]) -> u8 {
-        use core::cmp::{Equal, Less, Greater};
+        use core::cmp::Ordering::{Equal, Less, Greater};
         match r.binary_search(|&(lo, hi, _, _)| {
             if lo <= c && c <= hi { Equal }
             else if hi < c { Less }
@@ -530,7 +532,7 @@ def comp_pfun(char):
 
     f.write("""
     fn bsearch_range_value_table(c: char, r: &'static [(char, char, u8)]) -> u8 {
-        use core::cmp::{Equal, Less, Greater};
+        use core::cmp::Ordering::{Equal, Less, Greater};
         use core::slice::SlicePrelude;
         use core::slice;
         match r.binary_search(|&(lo, hi, _)| {

src/liballoc/arc.rs

@@ -22,7 +22,8 @@ use core::kinds::{Sync, Send};
 use core::mem::{min_align_of, size_of, drop};
 use core::mem;
 use core::ops::{Drop, Deref};
-use core::option::{Some, None, Option};
+use core::option::Option;
+use core::option::Option::{Some, None};
 use core::ptr::RawPtr;
 use core::ptr;
 use heap::deallocate;
@@ -326,7 +327,8 @@ mod tests {
     use std::comm::channel;
     use std::mem::drop;
     use std::ops::Drop;
-    use std::option::{Option, Some, None};
+    use std::option::Option;
+    use std::option::Option::{Some, None};
     use std::str::Str;
     use std::sync::atomic;
     use std::task;

src/liballoc/boxed.rs

@@ -19,7 +19,8 @@ use core::kinds::Sized;
 use core::mem;
 use core::option::Option;
 use core::raw::TraitObject;
-use core::result::{Ok, Err, Result};
+use core::result::Result;
+use core::result::Result::{Ok, Err};
 
 /// A value that represents the global exchange heap. This is the default
 /// place that the `box` keyword allocates into when no place is supplied.

src/liballoc/heap.rs

@@ -125,7 +125,8 @@ const MIN_ALIGN: uint = 16;
 
 #[cfg(jemalloc)]
 mod imp {
-    use core::option::{None, Option};
+    use core::option::Option;
+    use core::option::Option::None;
     use core::ptr::{null_mut, null};
     use core::num::Int;
     use libc::{c_char, c_int, c_void, size_t};

src/liballoc/rc.rs

@@ -149,10 +149,12 @@ use core::fmt;
 use core::kinds::marker;
 use core::mem::{transmute, min_align_of, size_of, forget};
 use core::ops::{Deref, Drop};
-use core::option::{Option, Some, None};
+use core::option::Option;
+use core::option::Option::{Some, None};
 use core::ptr;
 use core::ptr::RawPtr;
-use core::result::{Result, Ok, Err};
+use core::result::Result;
+use core::result::Result::{Ok, Err};
 
 use heap::deallocate;
 
@@ -739,8 +741,9 @@ impl<T> RcBoxPtr<T> for Weak<T> {
 mod tests {
     use super::{Rc, Weak, weak_count, strong_count};
     use std::cell::RefCell;
-    use std::option::{Option, Some, None};
-    use std::result::{Err, Ok};
+    use std::option::Option;
+    use std::option::Option::{Some, None};
+    use std::result::Result::{Err, Ok};
     use std::mem::drop;
     use std::clone::Clone;
 

src/libcollections/str.rs

@@ -825,8 +825,10 @@ mod tests {
     use std::default::Default;
     use std::char::Char;
     use std::clone::Clone;
-    use std::cmp::{Equal, Greater, Less, Ord, PartialOrd, Equiv};
-    use std::option::{Some, None};
+    use std::cmp::{Ord, PartialOrd, Equiv};
+    use std::cmp::Ordering::{Equal, Greater, Less};
+    use std::option::Option;
+    use std::option::Option::{Some, None};
     use std::ptr::RawPtr;
     use std::iter::{Iterator, IteratorExt, DoubleEndedIteratorExt};
 

src/libcore/any.rs

@@ -72,7 +72,8 @@
 #![stable]
 
 use mem::{transmute};
-use option::{Option, Some, None};
+use option::Option;
+use option::Option::{Some, None};
 use raw::TraitObject;
 use intrinsics::TypeId;
 

src/libcore/cell.rs

@@ -160,7 +160,8 @@ use cmp::PartialEq;
 use default::Default;
 use kinds::{marker, Copy};
 use ops::{Deref, DerefMut, Drop};
-use option::{None, Option, Some};
+use option::Option;
+use option::Option::{None, Some};
 
 /// A mutable memory location that admits only `Copy` data.
 #[unstable = "likely to be renamed; otherwise stable"]

src/libcore/char.rs

@@ -16,7 +16,8 @@
 #![doc(primitive = "char")]
 
 use mem::transmute;
-use option::{None, Option, Some};
+use option::Option;
+use option::Option::{None, Some};
 use iter::{range_step, Iterator, RangeStep};
 use slice::SlicePrelude;
 

src/libcore/cmp.rs

@@ -44,7 +44,8 @@
 pub use self::Ordering::*;
 
 use kinds::Sized;
-use option::{Option, Some, None};
+use option::Option;
+use option::Option::{Some, None};
 
 /// Trait for values that can be compared for equality and inequality.
 ///
@@ -288,10 +289,11 @@ pub fn partial_max<T: PartialOrd>(v1: T, v2: T) -> Option<T> {
 
 // Implementation of PartialEq, Eq, PartialOrd and Ord for primitive types
 mod impls {
-    use cmp::{PartialOrd, Ord, PartialEq, Eq, Ordering,
-              Less, Greater, Equal};
+    use cmp::{PartialOrd, Ord, PartialEq, Eq, Ordering};
+    use cmp::Ordering::{Less, Greater, Equal};
     use kinds::Sized;
-    use option::{Option, Some, None};
+    use option::Option;
+    use option::Option::{Some, None};
 
     macro_rules! partial_eq_impl(
         ($($t:ty)*) => ($(

src/libcore/fmt/float.rs

@@ -20,7 +20,7 @@ use fmt;
 use iter::{range, DoubleEndedIteratorExt};
 use num::{Float, FPNaN, FPInfinite, ToPrimitive};
 use num::cast;
-use result::Ok;
+use result::Result::Ok;
 use slice::{mod, SlicePrelude};
 use str::StrPrelude;
 

src/libcore/fmt/mod.rs

@@ -17,9 +17,10 @@ use cell::{Cell, Ref, RefMut};
 use iter::{Iterator, IteratorExt, range};
 use kinds::{Copy, Sized};
 use mem;
-use option::{Option, Some, None};
+use option::Option;
+use option::Option::{Some, None};
 use ops::Deref;
-use result::{Ok, Err};
+use result::Result::{Ok, Err};
 use result;
 use slice::SlicePrelude;
 use slice;

src/libcore/iter.rs

@@ -62,7 +62,8 @@ use cmp::Ord;
 use mem;
 use num::{ToPrimitive, Int};
 use ops::{Add, Deref};
-use option::{Option, Some, None};
+use option::Option;
+use option::Option::{Some, None};
 use uint;
 
 #[deprecated = "renamed to Extend"] pub use self::Extend as Extendable;
@@ -2427,7 +2428,9 @@ pub fn repeat<T: Clone>(elt: T) -> Repeat<T> {
 pub mod order {
     use cmp;
     use cmp::{Eq, Ord, PartialOrd, PartialEq};
-    use option::{Option, Some, None};
+    use cmp::Ordering::{Equal, Less, Greater};
+    use option::Option;
+    use option::Option::{Some, None};
     use super::Iterator;
 
     /// Compare `a` and `b` for equality using `Eq`
@@ -2445,11 +2448,11 @@ pub mod order {
     pub fn cmp<A: Ord, T: Iterator<A>, S: Iterator<A>>(mut a: T, mut b: S) -> cmp::Ordering {
         loop {
             match (a.next(), b.next()) {
-                (None, None) => return cmp::Equal,
-                (None, _   ) => return cmp::Less,
-                (_   , None) => return cmp::Greater,
+                (None, None) => return Equal,
+                (None, _   ) => return Less,
+                (_   , None) => return Greater,
                 (Some(x), Some(y)) => match x.cmp(&y) {
-                    cmp::Equal => (),
+                    Equal => (),
                     non_eq => return non_eq,
                 },
             }
@@ -2461,11 +2464,11 @@ pub mod order {
             -> Option<cmp::Ordering> {
         loop {
             match (a.next(), b.next()) {
-                (None, None) => return Some(cmp::Equal),
-                (None, _   ) => return Some(cmp::Less),
-                (_   , None) => return Some(cmp::Greater),
+                (None, None) => return Some(Equal),
+                (None, _   ) => return Some(Less),
+                (_   , None) => return Some(Greater),
                 (Some(x), Some(y)) => match x.partial_cmp(&y) {
-                    Some(cmp::Equal) => (),
+                    Some(Equal) => (),
                     non_eq => return non_eq,
                 },
             }

src/libcore/num/mod.rs

@@ -30,7 +30,8 @@ use kinds::Copy;
 use mem::size_of;
 use ops::{Add, Sub, Mul, Div, Rem, Neg};
 use ops::{Not, BitAnd, BitOr, BitXor, Shl, Shr};
-use option::{Option, Some, None};
+use option::Option;
+use option::Option::{Some, None};
 use str::{FromStr, from_str, StrPrelude};
 
 /// Simultaneous division and remainder

src/libcore/option.rs

@@ -149,7 +149,8 @@ use cmp::{Eq, Ord};
 use default::Default;
 use iter::{Iterator, IteratorExt, DoubleEndedIterator, FromIterator, ExactSizeIterator};
 use mem;
-use result::{Result, Ok, Err};
+use result::Result;
+use result::Result::{Ok, Err};
 use slice;
 use slice::AsSlice;
 use clone::Clone;

src/libcore/ptr.rs

@@ -90,9 +90,12 @@
 use mem;
 use clone::Clone;
 use intrinsics;
-use option::{Some, None, Option};
+use option::Option;
+use option::Option::{Some, None};
 
-use cmp::{PartialEq, Eq, PartialOrd, Equiv, Ordering, Less, Equal, Greater};
+use cmp::{PartialEq, Eq, PartialOrd, Equiv};
+use cmp::Ordering;
+use cmp::Ordering::{Less, Equal, Greater};
 
 pub use intrinsics::copy_memory;
 pub use intrinsics::copy_nonoverlapping_memory;

src/libcore/result.rs

@@ -236,7 +236,8 @@ use std::fmt::Show;
 use slice;
 use slice::AsSlice;
 use iter::{Iterator, IteratorExt, DoubleEndedIterator, FromIterator, ExactSizeIterator};
-use option::{None, Option, Some};
+use option::Option;
+use option::Option::{None, Some};
 
 /// `Result` is a type that represents either success (`Ok`) or failure (`Err`).
 ///

src/libcore/slice.rs

@@ -36,13 +36,15 @@
 
 use mem::transmute;
 use clone::Clone;
-use cmp::{PartialEq, PartialOrd, Eq, Ord, Ordering, Less, Equal, Greater, Equiv};
+use cmp::{Ordering, PartialEq, PartialOrd, Eq, Ord, Equiv};
+use cmp::Ordering::{Less, Equal, Greater};
 use cmp;
 use default::Default;
 use iter::*;
 use num::Int;
 use ops;
-use option::{None, Option, Some};
+use option::Option;
+use option::Option::{None, Some};
 use ptr;
 use ptr::RawPtr;
 use mem;
@@ -1702,7 +1704,8 @@ pub mod raw {
     use mem::transmute;
     use ptr::RawPtr;
     use raw::Slice;
-    use option::{None, Option, Some};
+    use option::Option;
+    use option::Option::{None, Some};
 
     /// Form a slice from a pointer and length (as a number of units,
     /// not bytes).

src/libcore/str.rs

@@ -29,7 +29,8 @@ use iter::range;
 use kinds::Sized;
 use mem;
 use num::Int;
-use option::{Option, None, Some};
+use option::Option;
+use option::Option::{None, Some};
 use ptr::RawPtr;
 use raw::{Repr, Slice};
 use slice::{mod, SlicePrelude};
@@ -1209,9 +1210,11 @@ Section: Trait implementations
 
 #[allow(missing_docs)]
 pub mod traits {
-    use cmp::{Ord, Ordering, Less, Equal, Greater, PartialEq, PartialOrd, Equiv, Eq};
+    use cmp::{Ordering, Ord, PartialEq, PartialOrd, Equiv, Eq};
+    use cmp::Ordering::{Less, Equal, Greater};
     use iter::IteratorExt;
-    use option::{Option, Some};
+    use option::Option;
+    use option::Option::Some;
     use ops;
     use str::{Str, StrPrelude, eq_slice};
 

src/libcore/tuple/mod.rs

@@ -69,7 +69,8 @@ pub use unit;
 use clone::Clone;
 use cmp::*;
 use default::Default;
-use option::{Option, Some};
+use option::Option;
+use option::Option::Some;
 
 // macro for implementing n-ary tuple functions and operations
 macro_rules! tuple_impls {