libcollections: convert `BTreeSet` binops to by value

diff --git a/src/libcollections/btree/set.rs b/src/libcollections/btree/set.rs
index cd01c008fe1bc3a92654950c7ebc06dc2f4e1a7b..d4c05e4b7d39c327281689ec7632b14d15b4d3ea 100644 (file)
--- a/src/libcollections/btree/set.rs
+++ b/src/libcollections/btree/set.rs
@@ -409,6 +409,8 @@ fn default() -> BTreeSet<T> {
 }
 
 #[unstable = "matches collection reform specification, waiting for dust to settle"]
+// NOTE(stage0): Remove impl after a snapshot
+#[cfg(stage0)]
 impl<T: Ord + Clone> Sub<BTreeSet<T>,BTreeSet<T>> for BTreeSet<T> {
     /// Returns the difference of `self` and `rhs` as a new `BTreeSet<T>`.
     ///
@@ -430,6 +432,30 @@ fn sub(&self, rhs: &BTreeSet<T>) -> BTreeSet<T> {
 }
 
 #[unstable = "matches collection reform specification, waiting for dust to settle"]
+#[cfg(not(stage0))]  // NOTE(stage0): Remove cfg after a snapshot
+impl<'a, 'b, T: Ord + Clone> Sub<&'b BTreeSet<T>, BTreeSet<T>> for &'a BTreeSet<T> {
+    /// Returns the difference of `self` and `rhs` as a new `BTreeSet<T>`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::BTreeSet;
+    ///
+    /// let a: BTreeSet<int> = vec![1, 2, 3].into_iter().collect();
+    /// let b: BTreeSet<int> = vec![3, 4, 5].into_iter().collect();
+    ///
+    /// let result: BTreeSet<int> = &a - &b;
+    /// let result_vec: Vec<int> = result.into_iter().collect();
+    /// assert_eq!(result_vec, vec![1, 2]);
+    /// ```
+    fn sub(self, rhs: &BTreeSet<T>) -> BTreeSet<T> {
+        self.difference(rhs).cloned().collect()
+    }
+}
+
+#[unstable = "matches collection reform specification, waiting for dust to settle"]
+// NOTE(stage0): Remove impl after a snapshot
+#[cfg(stage0)]
 impl<T: Ord + Clone> BitXor<BTreeSet<T>,BTreeSet<T>> for BTreeSet<T> {
     /// Returns the symmetric difference of `self` and `rhs` as a new `BTreeSet<T>`.
     ///
@@ -451,6 +477,30 @@ fn bitxor(&self, rhs: &BTreeSet<T>) -> BTreeSet<T> {
 }
 
 #[unstable = "matches collection reform specification, waiting for dust to settle"]
+#[cfg(not(stage0))]  // NOTE(stage0): Remove cfg after a snapshot
+impl<'a, 'b, T: Ord + Clone> BitXor<&'b BTreeSet<T>, BTreeSet<T>> for &'a BTreeSet<T> {
+    /// Returns the symmetric difference of `self` and `rhs` as a new `BTreeSet<T>`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::BTreeSet;
+    ///
+    /// let a: BTreeSet<int> = vec![1, 2, 3].into_iter().collect();
+    /// let b: BTreeSet<int> = vec![2, 3, 4].into_iter().collect();
+    ///
+    /// let result: BTreeSet<int> = &a ^ &b;
+    /// let result_vec: Vec<int> = result.into_iter().collect();
+    /// assert_eq!(result_vec, vec![1, 4]);
+    /// ```
+    fn bitxor(self, rhs: &BTreeSet<T>) -> BTreeSet<T> {
+        self.symmetric_difference(rhs).cloned().collect()
+    }
+}
+
+#[unstable = "matches collection reform specification, waiting for dust to settle"]
+// NOTE(stage0): Remove impl after a snapshot
+#[cfg(stage0)]
 impl<T: Ord + Clone> BitAnd<BTreeSet<T>,BTreeSet<T>> for BTreeSet<T> {
     /// Returns the intersection of `self` and `rhs` as a new `BTreeSet<T>`.
     ///
@@ -472,6 +522,30 @@ fn bitand(&self, rhs: &BTreeSet<T>) -> BTreeSet<T> {
 }
 
 #[unstable = "matches collection reform specification, waiting for dust to settle"]
+#[cfg(not(stage0))]  // NOTE(stage0): Remove cfg after a snapshot
+impl<'a, 'b, T: Ord + Clone> BitAnd<&'b BTreeSet<T>, BTreeSet<T>> for &'a BTreeSet<T> {
+    /// Returns the intersection of `self` and `rhs` as a new `BTreeSet<T>`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::BTreeSet;
+    ///
+    /// let a: BTreeSet<int> = vec![1, 2, 3].into_iter().collect();
+    /// let b: BTreeSet<int> = vec![2, 3, 4].into_iter().collect();
+    ///
+    /// let result: BTreeSet<int> = &a & &b;
+    /// let result_vec: Vec<int> = result.into_iter().collect();
+    /// assert_eq!(result_vec, vec![2, 3]);
+    /// ```
+    fn bitand(self, rhs: &BTreeSet<T>) -> BTreeSet<T> {
+        self.intersection(rhs).cloned().collect()
+    }
+}
+
+#[unstable = "matches collection reform specification, waiting for dust to settle"]
+// NOTE(stage0): Remove impl after a snapshot
+#[cfg(stage0)]
 impl<T: Ord + Clone> BitOr<BTreeSet<T>,BTreeSet<T>> for BTreeSet<T> {
     /// Returns the union of `self` and `rhs` as a new `BTreeSet<T>`.
     ///
@@ -492,6 +566,28 @@ fn bitor(&self, rhs: &BTreeSet<T>) -> BTreeSet<T> {
     }
 }
 
+#[unstable = "matches collection reform specification, waiting for dust to settle"]
+#[cfg(not(stage0))]  // NOTE(stage0): Remove cfg after a snapshot
+impl<'a, 'b, T: Ord + Clone> BitOr<&'b BTreeSet<T>, BTreeSet<T>> for &'a BTreeSet<T> {
+    /// Returns the union of `self` and `rhs` as a new `BTreeSet<T>`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::BTreeSet;
+    ///
+    /// let a: BTreeSet<int> = vec![1, 2, 3].into_iter().collect();
+    /// let b: BTreeSet<int> = vec![3, 4, 5].into_iter().collect();
+    ///
+    /// let result: BTreeSet<int> = &a | &b;
+    /// let result_vec: Vec<int> = result.into_iter().collect();
+    /// assert_eq!(result_vec, vec![1, 2, 3, 4, 5]);
+    /// ```
+    fn bitor(self, rhs: &BTreeSet<T>) -> BTreeSet<T> {
+        self.union(rhs).cloned().collect()
+    }
+}
+
 impl<T: Show> Show for BTreeSet<T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         try!(write!(f, "{{"));