Adjust Index/IndexMut impls. For generic collections, we take

references. For collections whose keys are integers, we take both
references and by-value.

1 files changed, 78 insertions, 0 deletions

diff --git a/src/libcore/str/mod.rs b/src/libcore/str/mod.rs
index e8181395b5c..b9a655c6d4e 100644
--- a/src/libcore/str/mod.rs
+++ b/src/libcore/str/mod.rs
@@ -1203,6 +1203,7 @@ mod traits {
     /// // byte 100 is outside the string
     /// // &s[3 .. 100];
     /// ```
+    #[cfg(stage0)]
     #[stable(feature = "rust1", since = "1.0.0")]
     impl ops::Index<ops::Range<usize>> for str {
         type Output = str;
@@ -1219,6 +1220,49 @@ 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.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// 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];
+    /// ```
+    #[cfg(not(stage0))]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    impl ops::Index<ops::Range<usize>> for str {
+        type Output = str;
+        #[inline]
+        fn index(&self, index: ops::Range<usize>) -> &str {
+            // 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`.
     ///
@@ -1229,6 +1273,8 @@ mod traits {
     #[stable(feature = "rust1", since = "1.0.0")]
     impl ops::Index<ops::RangeTo<usize>> for str {
         type Output = str;
+
+        #[cfg(stage0)]
         #[inline]
         fn index(&self, index: &ops::RangeTo<usize>) -> &str {
             // is_char_boundary checks that the index is in [0, .len()]
@@ -1238,6 +1284,17 @@ mod traits {
                 super::slice_error_fail(self, 0, index.end)
             }
         }
+
+        #[cfg(not(stage0))]
+        #[inline]
+        fn index(&self, index: ops::RangeTo<usize>) -> &str {
+            // 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.
@@ -1249,6 +1306,8 @@ mod traits {
     #[stable(feature = "rust1", since = "1.0.0")]
     impl ops::Index<ops::RangeFrom<usize>> for str {
         type Output = str;
+
+        #[cfg(stage0)]
         #[inline]
         fn index(&self, index: &ops::RangeFrom<usize>) -> &str {
             // is_char_boundary checks that the index is in [0, .len()]
@@ -1258,15 +1317,34 @@ mod traits {
                 super::slice_error_fail(self, index.start, self.len())
             }
         }
+
+        #[cfg(not(stage0))]
+        #[inline]
+        fn index(&self, index: ops::RangeFrom<usize>) -> &str {
+            // 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(feature = "rust1", since = "1.0.0")]
     impl ops::Index<ops::RangeFull> for str {
         type Output = str;
+
+        #[cfg(stage0)]
         #[inline]
         fn index(&self, _index: &ops::RangeFull) -> &str {
             self
         }
+
+        #[cfg(not(stage0))]
+        #[inline]
+        fn index(&self, _index: ops::RangeFull) -> &str {
+            self
+        }
     }
 }