doc: Remove documentation on newtype enums.

Author: pcwalton

doc/tutorial.md

@@ -681,45 +681,6 @@ the value of `North` is 0, `East` is 1, `South` is 2, and `West` is 3.
 When an enum is C-like, you can apply the `as` cast operator to
 convert it to its discriminator value as an `int`.
 
-<a name="single_variant_enum"></a>
-
-There is a special case for enums with a single variant, which are
-sometimes called "newtype-style enums" (after Haskell's "newtype"
-feature). These are used to define new types in such a way that the
-new name is not just a synonym for an existing type, but its own
-distinct type: `type` creates a structural synonym, while this form of
-`enum` creates a nominal synonym. If you say:
-
-~~~~
-enum GizmoId = int;
-~~~~
-
-That is a shorthand for this:
-
-~~~~
-enum GizmoId { GizmoId(int) }
-~~~~
-
-You can extract the contents of such an enum type with the
-dereference (`*`) unary operator:
-
-~~~~
-# enum GizmoId = int;
-let my_gizmo_id: GizmoId = GizmoId(10);
-let id_int: int = *my_gizmo_id;
-~~~~
-
-Types like this can be useful to differentiate between data that have
-the same type but must be used in different ways.
-
-~~~~
-enum Inches = int;
-enum Centimeters = int;
-~~~~
-
-The above definitions allow for a simple way for programs to avoid
-confusing numbers that correspond to different units.
-
 For enum types with multiple variants, destructuring is the only way to
 get at their contents. All variant constructors can be used as
 patterns, as in this definition of `area`:
@@ -789,10 +750,10 @@ match mytup {
 
 ## Tuple structs
 
-Rust also has _nominal tuples_, which behave like both structs and tuples,
-except that nominal tuple types have names
-(so `Foo(1, 2)` has a different type from `Bar(1, 2)`),
-and nominal tuple types' _fields_ do not have names.
+Rust also has _tuple structs_, which behave like both structs and tuples,
+except that, unlike tuples, tuple structs have names (so `Foo(1, 2)` has a
+different type from `Bar(1, 2)`), and tuple structs' _fields_ do not have
+names.
 
 For example:
 ~~~~
@@ -803,6 +764,37 @@ match mytup {
 }
 ~~~~
 
+<a name="newtype"></a>
+
+There is a special case for tuple structs with a single field, which are
+sometimes called "newtypes" (after Haskell's "newtype" feature). These are
+used to define new types in such a way that the new name is not just a
+synonym for an existing type but is rather its own distinct type.
+
+~~~~
+struct GizmoId(int);
+~~~~
+
+For convenience, you can extract the contents of such a struct with the
+dereference (`*`) unary operator:
+
+~~~~
+# struct GizmoId(int);
+let my_gizmo_id: GizmoId = GizmoId(10);
+let id_int: int = *my_gizmo_id;
+~~~~
+
+Types like this can be useful to differentiate between data that have
+the same type but must be used in different ways.
+
+~~~~
+struct Inches(int);
+struct Centimeters(int);
+~~~~
+
+The above definitions allow for a simple way for programs to avoid
+confusing numbers that correspond to different units.
+
 # Functions
 
 We've already seen several function definitions. Like all other static
@@ -2294,7 +2286,7 @@ struct level. Note that fields and methods are _public_ by default.
 pub mod farm {
 # pub type Chicken = int;
 # type Cow = int;
-# enum Human = int;
+# struct Human(int);
 # impl Human { fn rest(&self) { } }
 # pub fn make_me_a_farm() -> Farm { Farm { chickens: ~[], cows: ~[], farmer: Human(0) } }
     pub struct Farm {