Provide unzip method for Iterables, Arrays and Sequences of pairs.

#KT-5793 Fixed

libraries/stdlib/src/kotlin/collections/Operations.kt

@@ -32,3 +32,48 @@ public fun <T> Array<Array<out T>>.flatten(): List<T> {
     return result
 }
 
+/**
+ * Returns a pair of lists, where
+ * *first* list is built from the first values of each pair from this collection,
+ * *second* list is built from the second values of each pair from this collection.
+ */
+public fun <T, R> Iterable<Pair<T, R>>.unzip(): Pair<List<T>, List<R>> {
+    val expectedSize = collectionSizeOrDefault(10)
+    val listT = ArrayList<T>(expectedSize)
+    val listR = ArrayList<R>(expectedSize)
+    for (pair in this) {
+        listT.add(pair.first)
+        listR.add(pair.second)
+    }
+    return listT to listR
+}
+
+/**
+ * Returns a pair of lists, where
+ * *first* list is built from the first values of each pair from this array,
+ * *second* list is built from the second values of each pair from this array.
+ */
+public fun <T, R> Array<Pair<T, R>>.unzip(): Pair<List<T>, List<R>> {
+    val listT = ArrayList<T>(size())
+    val listR = ArrayList<R>(size())
+    for (pair in this) {
+        listT.add(pair.first)
+        listR.add(pair.second)
+    }
+    return listT to listR
+}
+
+/**
+ * Returns a pair of lists, where
+ * *first* list is built from the first values of each pair from this sequence,
+ * *second* list is built from the second values of each pair from this sequence.
+ */
+public fun <T, R> Sequence<Pair<T, R>>.unzip(): Pair<List<T>, List<R>> {
+    val listT = ArrayList<T>()
+    val listR = ArrayList<R>()
+    for (pair in this) {
+        listT.add(pair.first)
+        listR.add(pair.second)
+    }
+    return listT to listR
+}