Deprecate slicing methods in favor of notation

This commit deprecates `slice`, `slice_from`, `slice_to` and their
mutable variants in favor of slice notation.

The `as_slice` methods are left intact, for now.

[breaking-change]

2 files changed, 87 insertions, 91 deletions

diff --git a/src/libcore/slice.rs b/src/libcore/slice.rs
index 50cbb7a61dc..f02804ad9d1 100644
--- a/src/libcore/slice.rs
+++ b/src/libcore/slice.rs
@@ -67,9 +67,6 @@ use raw::Slice as RawSlice;
 pub trait SliceExt {
     type Item;
 
-    fn slice<'a>(&'a self, start: uint, end: uint) -> &'a [Self::Item];
-    fn slice_from<'a>(&'a self, start: uint) -> &'a [Self::Item];
-    fn slice_to<'a>(&'a self, end: uint) -> &'a [Self::Item];
     fn split_at<'a>(&'a self, mid: uint) -> (&'a [Self::Item], &'a [Self::Item]);
     fn iter<'a>(&'a self) -> Iter<'a, Self::Item>;
     fn split<'a, P>(&'a self, pred: P) -> Split<'a, Self::Item, P>
@@ -93,9 +90,6 @@ pub trait SliceExt {
     fn is_empty(&self) -> bool { self.len() == 0 }
     fn get_mut<'a>(&'a mut self, index: uint) -> Option<&'a mut Self::Item>;
     fn as_mut_slice<'a>(&'a mut self) -> &'a mut [Self::Item];
-    fn slice_mut<'a>(&'a mut self, start: uint, end: uint) -> &'a mut [Self::Item];
-    fn slice_from_mut<'a>(&'a mut self, start: uint) -> &'a mut [Self::Item];
-    fn slice_to_mut<'a>(&'a mut self, end: uint) -> &'a mut [Self::Item];
     fn iter_mut<'a>(&'a mut self) -> IterMut<'a, Self::Item>;
     fn first_mut<'a>(&'a mut self) -> Option<&'a mut Self::Item>;
     fn tail_mut<'a>(&'a mut self) -> &'a mut [Self::Item];
@@ -136,28 +130,6 @@ impl<T> SliceExt for [T] {
     type Item = T;
 
     #[inline]
-    fn slice(&self, start: uint, end: uint) -> &[T] {
-        assert!(start <= end);
-        assert!(end <= self.len());
-        unsafe {
-            transmute(RawSlice {
-                data: self.as_ptr().offset(start as int),
-                len: (end - start)
-            })
-        }
-    }
-
-    #[inline]
-    fn slice_from(&self, start: uint) -> &[T] {
-        self.slice(start, self.len())
-    }
-
-    #[inline]
-    fn slice_to(&self, end: uint) -> &[T] {
-        self.slice(0, end)
-    }
-
-    #[inline]
     fn split_at(&self, mid: uint) -> (&[T], &[T]) {
         (&self[..mid], &self[mid..])
     }
@@ -291,20 +263,6 @@ impl<T> SliceExt for [T] {
     #[inline]
     fn as_mut_slice(&mut self) -> &mut [T] { self }
 
-    fn slice_mut(&mut self, start: uint, end: uint) -> &mut [T] {
-        ops::IndexMut::index_mut(self, &ops::Range { start: start, end: end } )
-    }
-
-    #[inline]
-    fn slice_from_mut(&mut self, start: uint) -> &mut [T] {
-        ops::IndexMut::index_mut(self, &ops::RangeFrom { start: start } )
-    }
-
-    #[inline]
-    fn slice_to_mut(&mut self, end: uint) -> &mut [T] {
-        ops::IndexMut::index_mut(self, &ops::RangeTo { end: end } )
-    }
-
     #[inline]
     fn split_at_mut(&mut self, mid: uint) -> (&mut [T], &mut [T]) {
         unsafe {
@@ -345,13 +303,13 @@ impl<T> SliceExt for [T] {
 
     #[inline]
     fn tail_mut(&mut self) -> &mut [T] {
-        self.slice_from_mut(1)
+        &mut self[1 ..]
     }
 
     #[inline]
     fn init_mut(&mut self) -> &mut [T] {
         let len = self.len();
-        self.slice_to_mut(len-1)
+        &mut self[.. (len - 1)]
     }
 
     #[inline]
@@ -483,7 +441,7 @@ impl<T> SliceExt for [T] {
         self.swap(j, i-1);
 
         // Step 4: Reverse the (previously) weakly decreasing part
-        self.slice_from_mut(i).reverse();
+        self[i..].reverse();
 
         true
     }
@@ -505,7 +463,7 @@ impl<T> SliceExt for [T] {
         }
 
         // Step 2: Reverse the weakly increasing part
-        self.slice_from_mut(i).reverse();
+        self[i..].reverse();
 
         // Step 3: Find the rightmost element equal to or bigger than the pivot (i-1)
         let mut j = self.len() - 1;
@@ -522,8 +480,8 @@ impl<T> SliceExt for [T] {
     #[inline]
     fn clone_from_slice(&mut self, src: &[T]) -> uint where T: Clone {
         let min = cmp::min(self.len(), src.len());
-        let dst = self.slice_to_mut(min);
-        let src = src.slice_to(min);
+        let dst = &mut self[.. min];
+        let src = &src[.. min];
         for i in range(0, min) {
             dst[i].clone_from(&src[i]);
         }
@@ -531,6 +489,7 @@ impl<T> SliceExt for [T] {
     }
 }
 
+#[stable]
 impl<T> ops::Index<uint> for [T] {
     type Output = T;
 
@@ -541,6 +500,7 @@ impl<T> ops::Index<uint> for [T] {
     }
 }
 
+#[stable]
 impl<T> ops::IndexMut<uint> for [T] {
     type Output = T;
 
@@ -551,6 +511,7 @@ impl<T> ops::IndexMut<uint> for [T] {
     }
 }
 
+#[stable]
 impl<T> ops::Index<ops::Range<uint>> for [T] {
     type Output = [T];
     #[inline]
@@ -565,6 +526,7 @@ impl<T> ops::Index<ops::Range<uint>> for [T] {
         }
     }
 }
+#[stable]
 impl<T> ops::Index<ops::RangeTo<uint>> for [T] {
     type Output = [T];
     #[inline]
@@ -572,6 +534,7 @@ impl<T> ops::Index<ops::RangeTo<uint>> for [T] {
         self.index(&ops::Range{ start: 0, end: index.end })
     }
 }
+#[stable]
 impl<T> ops::Index<ops::RangeFrom<uint>> for [T] {
     type Output = [T];
     #[inline]
@@ -579,6 +542,7 @@ impl<T> ops::Index<ops::RangeFrom<uint>> for [T] {
         self.index(&ops::Range{ start: index.start, end: self.len() })
     }
 }
+#[stable]
 impl<T> ops::Index<ops::FullRange> for [T] {
     type Output = [T];
     #[inline]
@@ -587,6 +551,7 @@ impl<T> ops::Index<ops::FullRange> for [T] {
     }
 }
 
+#[stable]
 impl<T> ops::IndexMut<ops::Range<uint>> for [T] {
     type Output = [T];
     #[inline]
@@ -601,6 +566,7 @@ impl<T> ops::IndexMut<ops::Range<uint>> for [T] {
         }
     }
 }
+#[stable]
 impl<T> ops::IndexMut<ops::RangeTo<uint>> for [T] {
     type Output = [T];
     #[inline]
@@ -608,6 +574,7 @@ impl<T> ops::IndexMut<ops::RangeTo<uint>> for [T] {
         self.index_mut(&ops::Range{ start: 0, end: index.end })
     }
 }
+#[stable]
 impl<T> ops::IndexMut<ops::RangeFrom<uint>> for [T] {
     type Output = [T];
     #[inline]
@@ -616,6 +583,7 @@ impl<T> ops::IndexMut<ops::RangeFrom<uint>> for [T] {
         self.index_mut(&ops::Range{ start: index.start, end: len })
     }
 }
+#[stable]
 impl<T> ops::IndexMut<ops::FullRange> for [T] {
     type Output = [T];
     #[inline]
@@ -1051,7 +1019,7 @@ impl<'a, T, P> Iterator for SplitMut<'a, T, P> where P: FnMut(&T) -> bool {
             Some(idx) => {
                 let tmp = mem::replace(&mut self.v, &mut []);
                 let (head, tail) = tmp.split_at_mut(idx);
-                self.v = tail.slice_from_mut(1);
+                self.v = &mut tail[1..];
                 Some(head)
             }
         }
@@ -1087,7 +1055,7 @@ impl<'a, T, P> DoubleEndedIterator for SplitMut<'a, T, P> where
                 let tmp = mem::replace(&mut self.v, &mut []);
                 let (head, tail) = tmp.split_at_mut(idx);
                 self.v = head;
-                Some(tail.slice_from_mut(1))
+                Some(&mut tail[1..])
             }
         }
     }
diff --git a/src/libcore/str/mod.rs b/src/libcore/str/mod.rs
index 6a542b2c458..42034a8bd70 100644
--- a/src/libcore/str/mod.rs
+++ b/src/libcore/str/mod.rs
@@ -902,13 +902,13 @@ impl<'a> Iterator for SplitStr<'a> {
 
         match self.it.next() {
             Some((from, to)) => {
-                let ret = Some(self.it.haystack.slice(self.last_end, from));
+                let ret = Some(&self.it.haystack[self.last_end .. from]);
                 self.last_end = to;
                 ret
             }
             None => {
                 self.finished = true;
-                Some(self.it.haystack.slice(self.last_end, self.it.haystack.len()))
+                Some(&self.it.haystack[self.last_end .. self.it.haystack.len()])
             }
         }
     }
@@ -1115,27 +1115,90 @@ mod traits {
         }
     }
 
+    /// Returns a slice of the given string from the byte range
+    /// [`begin`..`end`).
+    ///
+    /// This operation is `O(1)`.
+    ///
+    /// Panics when `begin` and `end` do not point to valid characters
+    /// or point beyond the last character of the string.
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// let s = "Löwe 老虎 Léopard";
+    /// assert_eq!(&s[0 .. 1], "L");
+    ///
+    /// assert_eq!(&s[1 .. 9], "öwe 老");
+    ///
+    /// // these will panic:
+    /// // byte 2 lies within `ö`:
+    /// // &s[2 ..3];
+    ///
+    /// // byte 8 lies within `老`
+    /// // &s[1 .. 8];
+    ///
+    /// // byte 100 is outside the string
+    /// // &s[3 .. 100];
+    /// ```
+    #[stable]
     impl ops::Index<ops::Range<uint>> for str {
         type Output = str;
         #[inline]
         fn index(&self, index: &ops::Range<uint>) -> &str {
-            self.slice(index.start, index.end)
+            // is_char_boundary checks that the index is in [0, .len()]
+            if index.start <= index.end &&
+               self.is_char_boundary(index.start) &&
+               self.is_char_boundary(index.end) {
+                unsafe { self.slice_unchecked(index.start, index.end) }
+            } else {
+                super::slice_error_fail(self, index.start, index.end)
+            }
         }
     }
+
+    /// Returns a slice of the string from the beginning to byte
+    /// `end`.
+    ///
+    /// Equivalent to `self[0 .. end]`.
+    ///
+    /// Panics when `end` does not point to a valid character, or is
+    /// out of bounds.
+    #[stable]
     impl ops::Index<ops::RangeTo<uint>> for str {
         type Output = str;
         #[inline]
         fn index(&self, index: &ops::RangeTo<uint>) -> &str {
-            self.slice_to(index.end)
+            // is_char_boundary checks that the index is in [0, .len()]
+            if self.is_char_boundary(index.end) {
+                unsafe { self.slice_unchecked(0, index.end) }
+            } else {
+                super::slice_error_fail(self, 0, index.end)
+            }
         }
     }
+
+    /// Returns a slice of the string from `begin` to its end.
+    ///
+    /// Equivalent to `self[begin .. self.len()]`.
+    ///
+    /// Panics when `begin` does not point to a valid character, or is
+    /// out of bounds.
+    #[stable]
     impl ops::Index<ops::RangeFrom<uint>> for str {
         type Output = str;
         #[inline]
         fn index(&self, index: &ops::RangeFrom<uint>) -> &str {
-            self.slice_from(index.start)
+            // is_char_boundary checks that the index is in [0, .len()]
+            if self.is_char_boundary(index.start) {
+                unsafe { self.slice_unchecked(index.start, self.len()) }
+            } else {
+                super::slice_error_fail(self, index.start, self.len())
+            }
         }
     }
+
+    #[stable]
     impl ops::Index<ops::FullRange> for str {
         type Output = str;
         #[inline]
@@ -1208,9 +1271,6 @@ pub trait StrExt {
     fn lines<'a>(&'a self) -> Lines<'a>;
     fn lines_any<'a>(&'a self) -> LinesAny<'a>;
     fn char_len(&self) -> uint;
-    fn slice<'a>(&'a self, begin: uint, end: uint) -> &'a str;
-    fn slice_from<'a>(&'a self, begin: uint) -> &'a str;
-    fn slice_to<'a>(&'a self, end: uint) -> &'a str;
     fn slice_chars<'a>(&'a self, begin: uint, end: uint) -> &'a str;
     unsafe fn slice_unchecked<'a>(&'a self, begin: uint, end: uint) -> &'a str;
     fn starts_with(&self, pat: &str) -> bool;
@@ -1332,7 +1392,7 @@ impl StrExt for str {
     fn lines_any(&self) -> LinesAny {
         fn f(line: &str) -> &str {
             let l = line.len();
-            if l > 0 && line.as_bytes()[l - 1] == b'\r' { line.slice(0, l - 1) }
+            if l > 0 && line.as_bytes()[l - 1] == b'\r' { &line[0 .. l - 1] }
             else { line }
         }
 
@@ -1343,38 +1403,6 @@ impl StrExt for str {
     #[inline]
     fn char_len(&self) -> uint { self.chars().count() }
 
-    #[inline]
-    fn slice(&self, begin: uint, end: uint) -> &str {
-        // is_char_boundary checks that the index is in [0, .len()]
-        if begin <= end &&
-           self.is_char_boundary(begin) &&
-           self.is_char_boundary(end) {
-            unsafe { self.slice_unchecked(begin, end) }
-        } else {
-            slice_error_fail(self, begin, end)
-        }
-    }
-
-    #[inline]
-    fn slice_from(&self, begin: uint) -> &str {
-        // is_char_boundary checks that the index is in [0, .len()]
-        if self.is_char_boundary(begin) {
-            unsafe { self.slice_unchecked(begin, self.len()) }
-        } else {
-            slice_error_fail(self, begin, self.len())
-        }
-    }
-
-    #[inline]
-    fn slice_to(&self, end: uint) -> &str {
-        // is_char_boundary checks that the index is in [0, .len()]
-        if self.is_char_boundary(end) {
-            unsafe { self.slice_unchecked(0, end) }
-        } else {
-            slice_error_fail(self, 0, end)
-        }
-    }
-
     fn slice_chars(&self, begin: uint, end: uint) -> &str {
         assert!(begin <= end);
         let mut count = 0;