Merge pull request #29006 from cruisediary/master

Author: swift-ci

docs/TypeChecker.rst

@@ -370,12 +370,12 @@ guesswork. However, we note that the type of an enum member actually
 has a regular structure. For example, consider the ``Optional`` type::
 
   enum Optional<T> {
-    case None
-    case Some(T)
+    case none
+    case some(T)
   }
 
-The type of ``Optional<T>.None`` is ``Optional<T>``, while the type of
-``Optional<T>.Some`` is ``(T) -> Optional<T>``. In fact, the
+The type of ``Optional<T>.none`` is ``Optional<T>``, while the type of
+``Optional<T>.some`` is ``(T) -> Optional<T>``. In fact, the
 type of an enum element can have one of two forms: it can be ``T0``,
 for an enum element that has no extra data, or it can be ``T2 -> T0``,
 where ``T2`` is the data associated with the enum element.  For the