Prelude: rename and consolidate extension traits

This commit renames a number of extension traits for slices and string
slices, now that they have been refactored for DST. In many cases,
multiple extension traits could now be consolidated. Further
consolidation will be possible with generalized where clauses.

The renamings are consistent with the [new `-Prelude`
suffix](rust-lang/rfcs#344). There are probably
a few more candidates for being renamed this way, but that is left for
API stabilization of the relevant modules.

Because this renames traits, it is a:

[breaking-change]

However, I do not expect any code that currently uses the standard
library to actually break.

Closes rust-lang#17917

Author: aturon

src/etc/unicode.py

@@ -293,7 +293,7 @@ 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::slice::ImmutableSlice;
+    use core::slice::SlicePrelude;
     r.binary_search(|&(lo,hi)| {
         if lo <= c && c <= hi { Equal }
         else if hi < c { Less }
@@ -351,7 +351,7 @@ def emit_conversions_module(f, lowerupper, upperlower):
     f.write("pub mod conversions {")
     f.write("""
     use core::cmp::{Equal, Less, Greater};
-    use core::slice::ImmutableSlice;
+    use core::slice::SlicePrelude;
     use core::tuple::Tuple2;
     use core::option::{Option, Some, None};
     use core::slice;
@@ -390,7 +390,7 @@ def emit_conversions_module(f, lowerupper, upperlower):
 
 def emit_grapheme_module(f, grapheme_table, grapheme_cats):
     f.write("""pub mod grapheme {
-    use core::slice::ImmutableSlice;
+    use core::slice::SlicePrelude;
     use core::slice;
 
     #[allow(non_camel_case_types)]
@@ -430,7 +430,7 @@ 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::slice::ImmutableSlice;\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 {
@@ -530,7 +530,7 @@ 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::slice::ImmutableSlice;
+        use core::slice::SlicePrelude;
         use core::slice;
         match r.binary_search(|&(lo, hi, _)| {
             if lo <= c && c <= hi { Equal }

src/libcollections/hash/mod.rs

@@ -290,7 +290,7 @@ mod tests {
     use core::kinds::Sized;
     use std::mem;
 
-    use slice::ImmutableSlice;
+    use slice::SlicePrelude;
     use super::{Hash, Hasher, Writer};
 
     struct MyWriterHasher;

src/libcollections/hash/sip.rs

@@ -273,7 +273,7 @@ mod tests {
 
     use str::Str;
     use string::String;
-    use slice::{AsSlice, ImmutableSlice};
+    use slice::{AsSlice, SlicePrelude};
     use vec::Vec;
 
     use super::super::{Hash, Writer};

src/libcollections/slice.rs

@@ -42,10 +42,10 @@
 //!
 //! ## Traits
 //!
-//! A number of traits add methods that allow you to accomplish tasks with slices.
-//! These traits include `ImmutableSlice`, which is defined for `&[T]` types,
-//! `MutableSlice`, defined for `&mut [T]` types, and `Slice` and `SliceMut`
-//! which are defined for `[T]`.
+//! A number of traits add methods that allow you to accomplish tasks
+//! with slices, the most important being `SlicePrelude`. Other traits
+//! apply only to slices of elements satisfying certain bounds (like
+//! `Ord`).
 //!
 //! An example is the `slice` method which enables slicing syntax `[a..b]` that
 //! returns an immutable "view" into a `Vec` or another slice from the index
@@ -99,11 +99,11 @@ use core::iter::{range_step, MultiplicativeIterator};
 
 use vec::Vec;
 
-pub use core::slice::{Chunks, AsSlice, ImmutableSlice, ImmutablePartialEqSlice};
-pub use core::slice::{ImmutableOrdSlice, MutableSlice, Items, MutItems};
+pub use core::slice::{Chunks, AsSlice, SlicePrelude, PartialEqSlicePrelude};
+pub use core::slice::{OrdSlicePrelude, SlicePrelude, Items, MutItems};
 pub use core::slice::{ImmutableIntSlice, MutableIntSlice};
 pub use core::slice::{MutSplits, MutChunks, Splits};
-pub use core::slice::{bytes, mut_ref_slice, ref_slice, MutableCloneableSlice};
+pub use core::slice::{bytes, mut_ref_slice, ref_slice, CloneSlicePrelude};
 pub use core::slice::{Found, NotFound};
 
 // Functional utilities
@@ -266,29 +266,13 @@ impl<T: Clone> Iterator<Vec<T>> for Permutations<T> {
     }
 }
 
-/// Extension methods for vector slices with cloneable elements
-pub trait CloneableVector<T> for Sized? {
-    /// Copies `self` into a new `Vec`.
-    fn to_vec(&self) -> Vec<T>;
-}
-
-impl<T: Clone> CloneableVector<T> for [T] {
-    /// Returns a copy of `v`.
-    #[inline]
-    fn to_vec(&self) -> Vec<T> {
-        let mut vector = Vec::with_capacity(self.len());
-        vector.push_all(self);
-        vector
-    }
-}
-
-#[experimental]
-pub trait BoxedSlice<T> {
+/// Extension methods for boxed slices.
+pub trait BoxedSlicePrelude<T> {
     /// Convert `self` into a vector without clones or allocation.
     fn into_vec(self) -> Vec<T>;
 }
 
-impl<T> BoxedSlice<T> for Box<[T]> {
+impl<T> BoxedSlicePrelude<T> for Box<[T]> {
     #[experimental]
     fn into_vec(mut self) -> Vec<T> {
         unsafe {
@@ -299,8 +283,11 @@ impl<T> BoxedSlice<T> for Box<[T]> {
     }
 }
 
-/// Extension methods for vectors containing `Clone` elements.
-pub trait ImmutableCloneableVector<T> for Sized? {
+/// Allocating extension methods for slices containing `Clone` elements.
+pub trait CloneSliceAllocPrelude<T> for Sized? {
+    /// Copies `self` into a new `Vec`.
+    fn to_vec(&self) -> Vec<T>;
+
     /// Partitions the vector into two vectors `(a, b)`, where all
     /// elements of `a` satisfy `f` and all elements of `b` do not.
     fn partitioned(&self, f: |&T| -> bool) -> (Vec<T>, Vec<T>);
@@ -332,7 +319,16 @@ pub trait ImmutableCloneableVector<T> for Sized? {
     fn permutations(&self) -> Permutations<T>;
 }
 
-impl<T: Clone> ImmutableCloneableVector<T> for [T] {
+impl<T: Clone> CloneSliceAllocPrelude<T> for [T] {
+    /// Returns a copy of `v`.
+    #[inline]
+    fn to_vec(&self) -> Vec<T> {
+        let mut vector = Vec::with_capacity(self.len());
+        vector.push_all(self);
+        vector
+    }
+
+
     #[inline]
     fn partitioned(&self, f: |&T| -> bool) -> (Vec<T>, Vec<T>) {
         let mut lefts  = Vec::new();
@@ -562,9 +558,36 @@ fn merge_sort<T>(v: &mut [T], compare: |&T, &T| -> Ordering) {
     }
 }
 
-/// Extension methods for vectors such that their elements are
-/// mutable.
-pub trait MutableSliceAllocating<T> for Sized? {
+/// Allocating extension methods for slices on Ord values.
+#[experimental = "likely to merge with other traits"]
+pub trait OrdSliceAllocPrelude<T> for Sized? {
+    /// Sorts the slice, in place.
+    ///
+    /// This is equivalent to `self.sort_by(|a, b| a.cmp(b))`.
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// let mut v = [-5i, 4, 1, -3, 2];
+    ///
+    /// v.sort();
+    /// assert!(v == [-5i, -3, 1, 2, 4]);
+    /// ```
+    #[experimental]
+    fn sort(&mut self);
+}
+
+impl<T: Ord> OrdSliceAllocPrelude<T> for [T] {
+    #[experimental]
+    #[inline]
+    fn sort(&mut self) {
+        self.sort_by(|a, b| a.cmp(b))
+    }
+}
+
+/// Allocating extension methods for slices.
+#[experimental = "likely to merge with other traits"]
+pub trait SliceAllocPrelude<T> for Sized? {
     /// Sorts the slice, in place, using `compare` to compare
     /// elements.
     ///
@@ -608,7 +631,7 @@ pub trait MutableSliceAllocating<T> for Sized? {
     fn move_from(&mut self, src: Vec<T>, start: uint, end: uint) -> uint;
 }
 
-impl<T> MutableSliceAllocating<T> for [T] {
+impl<T> SliceAllocPrelude<T> for [T] {
     #[inline]
     fn sort_by(&mut self, compare: |&T, &T| -> Ordering) {
         merge_sort(self, compare)
@@ -623,127 +646,6 @@ impl<T> MutableSliceAllocating<T> for [T] {
     }
 }
 
-/// Methods for mutable vectors with orderable elements, such as
-/// in-place sorting.
-pub trait MutableOrdSlice<T> for Sized? {
-    /// Sorts the slice, in place.
-    ///
-    /// This is equivalent to `self.sort_by(|a, b| a.cmp(b))`.
-    ///
-    /// # Example
-    ///
-    /// ```rust
-    /// let mut v = [-5i, 4, 1, -3, 2];
-    ///
-    /// v.sort();
-    /// assert!(v == [-5i, -3, 1, 2, 4]);
-    /// ```
-    fn sort(&mut self);
-
-    /// Mutates the slice to the next lexicographic permutation.
-    ///
-    /// Returns `true` if successful and `false` if the slice is at the
-    /// last-ordered permutation.
-    ///
-    /// # Example
-    ///
-    /// ```rust
-    /// let v: &mut [_] = &mut [0i, 1, 2];
-    /// v.next_permutation();
-    /// let b: &mut [_] = &mut [0i, 2, 1];
-    /// assert!(v == b);
-    /// v.next_permutation();
-    /// let b: &mut [_] = &mut [1i, 0, 2];
-    /// assert!(v == b);
-    /// ```
-    fn next_permutation(&mut self) -> bool;
-
-    /// Mutates the slice to the previous lexicographic permutation.
-    ///
-    /// Returns `true` if successful and `false` if the slice is at the
-    /// first-ordered permutation.
-    ///
-    /// # Example
-    ///
-    /// ```rust
-    /// let v: &mut [_] = &mut [1i, 0, 2];
-    /// v.prev_permutation();
-    /// let b: &mut [_] = &mut [0i, 2, 1];
-    /// assert!(v == b);
-    /// v.prev_permutation();
-    /// let b: &mut [_] = &mut [0i, 1, 2];
-    /// assert!(v == b);
-    /// ```
-    fn prev_permutation(&mut self) -> bool;
-}
-
-impl<T: Ord> MutableOrdSlice<T> for [T] {
-    #[inline]
-    fn sort(&mut self) {
-        self.sort_by(|a, b| a.cmp(b))
-    }
-
-    fn next_permutation(&mut self) -> bool {
-        // These cases only have 1 permutation each, so we can't do anything.
-        if self.len() < 2 { return false; }
-
-        // Step 1: Identify the longest, rightmost weakly decreasing part of the vector
-        let mut i = self.len() - 1;
-        while i > 0 && self[i-1] >= self[i] {
-            i -= 1;
-        }
-
-        // If that is the entire vector, this is the last-ordered permutation.
-        if i == 0 {
-            return false;
-        }
-
-        // Step 2: Find the rightmost element larger than the pivot (i-1)
-        let mut j = self.len() - 1;
-        while j >= i && self[j] <= self[i-1]  {
-            j -= 1;
-        }
-
-        // Step 3: Swap that element with the pivot
-        self.swap(j, i-1);
-
-        // Step 4: Reverse the (previously) weakly decreasing part
-        self[mut i..].reverse();
-
-        true
-    }
-
-    fn prev_permutation(&mut self) -> bool {
-        // These cases only have 1 permutation each, so we can't do anything.
-        if self.len() < 2 { return false; }
-
-        // Step 1: Identify the longest, rightmost weakly increasing part of the vector
-        let mut i = self.len() - 1;
-        while i > 0 && self[i-1] <= self[i] {
-            i -= 1;
-        }
-
-        // If that is the entire vector, this is the first-ordered permutation.
-        if i == 0 {
-            return false;
-        }
-
-        // Step 2: Reverse the weakly increasing part
-        self[mut i..].reverse();
-
-        // Step 3: Find the rightmost element equal to or bigger than the pivot (i-1)
-        let mut j = self.len() - 1;
-        while j >= i && self[j-1] < self[i-1]  {
-            j -= 1;
-        }
-
-        // Step 4: Swap that element with the pivot
-        self.swap(i-1, j);
-
-        true
-    }
-}
-
 /// Unsafe operations
 pub mod raw {
     pub use core::slice::raw::{buf_as_slice, mut_buf_as_slice};

src/libcollections/str.rs

@@ -56,8 +56,8 @@ use core::fmt;
 use core::cmp;
 use core::iter::AdditiveIterator;
 use core::kinds::Sized;
-use core::prelude::{Char, Clone, Eq, Equiv, ImmutableSlice};
-use core::prelude::{Iterator, MutableSlice, None, Option, Ord, Ordering};
+use core::prelude::{Char, Clone, Eq, Equiv};
+use core::prelude::{Iterator, SlicePrelude, None, Option, Ord, Ordering};
 use core::prelude::{PartialEq, PartialOrd, Result, AsSlice, Some, Tuple2};
 use core::prelude::{range};
 
@@ -73,8 +73,8 @@ pub use core::str::{CharSplitsN, AnyLines, MatchIndices, StrSplits};
 pub use core::str::{Utf16CodeUnits, eq_slice, is_utf8, is_utf16, Utf16Items};
 pub use core::str::{Utf16Item, ScalarValue, LoneSurrogate, utf16_items};
 pub use core::str::{truncate_utf16_at_nul, utf8_char_width, CharRange};
-pub use core::str::{Str, StrSlice};
-pub use unicode::str::{UnicodeStrSlice, Words, Graphemes, GraphemeIndices};
+pub use core::str::{Str, StrPrelude};
+pub use unicode::str::{UnicodeStrPrelude, Words, Graphemes, GraphemeIndices};
 
 /*
 Section: Creating a string
@@ -790,10 +790,10 @@ mod tests {
     use std::iter::{Iterator, DoubleEndedIterator};
 
     use super::*;
-    use std::slice::{AsSlice, ImmutableSlice};
+    use std::slice::{AsSlice, SlicePrelude};
     use string::String;
     use vec::Vec;
-    use slice::CloneableVector;
+    use slice::CloneSliceAllocPrelude;
 
     use unicode::char::UnicodeChar;
 
@@ -2240,8 +2240,8 @@ mod bench {
     use test::black_box;
     use super::*;
     use std::iter::{Iterator, DoubleEndedIterator};
-    use std::str::StrSlice;
-    use std::slice::ImmutableSlice;
+    use std::str::StrPrelude;
+    use std::slice::SlicePrelude;
 
     #[bench]
     fn char_iterator(b: &mut Bencher) {