Add doc aliases like BTreeMap/BTreeSet

Author: cuviper

src/map.rs

@@ -821,6 +821,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     /// This preserves the order of the remaining elements.
     ///
     /// Computes in **O(1)** time (average).
+    #[doc(alias = "pop_last")] // like `BTreeMap`
     pub fn pop(&mut self) -> Option<(K, V)> {
         self.core.pop()
     }
@@ -1087,6 +1088,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     /// Get the first key-value pair
     ///
     /// Computes in **O(1)** time.
+    #[doc(alias = "first_key_value")] // like `BTreeMap`
     pub fn first(&self) -> Option<(&K, &V)> {
         self.as_entries().first().map(Bucket::refs)
     }
@@ -1108,6 +1110,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     /// Get the last key-value pair
     ///
     /// Computes in **O(1)** time.
+    #[doc(alias = "last_key_value")] // like `BTreeMap`
     pub fn last(&self) -> Option<(&K, &V)> {
         self.as_entries().last().map(Bucket::refs)
     }

src/set.rs

@@ -708,6 +708,7 @@ impl<T, S> IndexSet<T, S> {
     /// This preserves the order of the remaining elements.
     ///
     /// Computes in **O(1)** time (average).
+    #[doc(alias = "pop_last")] // like `BTreeSet`
     pub fn pop(&mut self) -> Option<T> {
         self.map.pop().map(|(x, ())| x)
     }