rollup merge of #22286: nikomatsakis/variance-4b

Conflicts:
	src/librustc/middle/infer/combine.rs
	src/librustc_typeck/check/wf.rs

1 files changed, 5 insertions, 5 deletions

diff --git a/src/doc/reference.md b/src/doc/reference.md
index 3bbe60a77c9..db940947040 100644
--- a/src/doc/reference.md
+++ b/src/doc/reference.md
@@ -572,7 +572,7 @@ the final namespace qualifier is omitted.
 Two examples of paths with type arguments:
 
 ```
-# struct HashMap<K, V>;
+# struct HashMap<K, V>(K,V);
 # fn f() {
 # fn id<T>(t: T) -> T { t }
 type T = HashMap<i32,String>; // Type arguments used in a type expression
@@ -1599,7 +1599,7 @@ pointer values (pointing to a type for which an implementation of the given
 trait is in scope) to pointers to the trait name, used as a type.
 
 ```
-# trait Shape { }
+# trait Shape { fn dummy(&self) { } }
 # impl Shape for i32 { }
 # let mycircle = 0i32;
 let myshape: Box<Shape> = Box::new(mycircle) as Box<Shape>;
@@ -1630,8 +1630,8 @@ let x: f64 = Num::from_i32(42);
 Traits may inherit from other traits. For example, in
 
 ```
-trait Shape { fn area() -> f64; }
-trait Circle : Shape { fn radius() -> f64; }
+trait Shape { fn area(&self) -> f64; }
+trait Circle : Shape { fn radius(&self) -> f64; }
 ```
 
 the syntax `Circle : Shape` means that types that implement `Circle` must also
@@ -1725,7 +1725,7 @@ type parameters taken by the trait it implements. Implementation parameters
 are written after the `impl` keyword.
 
 ```
-# trait Seq<T> { }
+# trait Seq<T> { fn dummy(&self, _: T) { } }
 impl<T> Seq<T> for Vec<T> {
    /* ... */
 }