trivially identical updates

Author: vanvoorden

proposals/0494-add-is-identical-methods.md

@@ -57,22 +57,27 @@ let a = [1, 2, 3, 4]
 print(result(for: a))
 // Prints "computing new result"
 // Prints "[2, 4]"
+
 let b = a
 print(result(for: b))
 // Prints "computing new result"
 // Prints "[2, 4]"
+
 let c = [1, 2, 3, 4]
 print(result(for: c))
 // Prints "computing new result"
 // Prints "[2, 4]"
+
 let d = [1, 2, 3, 4, 5, 6]
 print(result(for: d))
 // Prints "computing new result"
 // Prints "[2, 4, 6]"
+
 let e = d
 print(result(for: e))
 // Prints "computing new result"
 // Prints "[2, 4, 6]"
+
 let f = [1, 2, 3, 4, 5, 6]
 print(result(for: f))
 // Prints "computing new result"
@@ -113,19 +118,24 @@ let a = [1, 2, 3, 4]
 print(memoizer.result(for: a))
 // Prints "computing new result"
 // Prints "[2, 4]"
+
 let b = a
 print(memoizer.result(for: b))
 // Prints "[2, 4]"
+
 let c = [1, 2, 3, 4]
 print(memoizer.result(for: c))
 // Prints "[2, 4]"
+
 let d = [1, 2, 3, 4, 5, 6]
 print(memoizer.result(for: d))
 // Prints "computing new result"
 // Prints "[2, 4, 6]"
+
 let e = d
 print(memoizer.result(for: e))
 // Prints "[2, 4, 6]"
+
 let f = [1, 2, 3, 4, 5, 6]
 print(memoizer.result(for: f))
 // Prints "[2, 4, 6]"