unignore and fix doctests in guide and reference

Author: Jorge Aparicio

src/doc/guide-testing.md

@@ -536,8 +536,9 @@ optimizer to consider the result used and ensures it cannot remove the
 computation entirely. This could be done for the example above by adjusting the
 `b.iter` call to
 
-```{rust,ignore}
-# struct X; impl X { fn iter<T>(&self, _: || -> T) {} } let b = X;
+```rust
+# struct X;
+# impl X { fn iter<T, F>(&self, _: F) where F: FnMut() -> T {} } let b = X;
 b.iter(|| {
     // note lack of `;` (could also use an explicit `return`).
     range(0u, 1000).fold(0, |old, new| old ^ new)
@@ -548,11 +549,12 @@ Or, the other option is to call the generic `test::black_box` function, which
 is an opaque "black box" to the optimizer and so forces it to consider any
 argument as used.
 
-```{rust,ignore}
+```rust
 extern crate test;
 
 # fn main() {
-# struct X; impl X { fn iter<T>(&self, _: || -> T) {} } let b = X;
+# struct X;
+# impl X { fn iter<T, F>(&self, _: F) where F: FnMut() -> T {} } let b = X;
 b.iter(|| {
     test::black_box(range(0u, 1000).fold(0, |old, new| old ^ new));
 });

src/doc/guide.md

@@ -4231,8 +4231,8 @@ arguments, really powerful things are possible.
 
 Let's make a closure:
 
-```{rust,ignore}
-let add_one = |x| { 1 + x };
+```{rust}
+let add_one = |&: x| { 1 + x };
 
 println!("The sum of 5 plus 1 is {}.", add_one(5));
 ```
@@ -4243,9 +4243,9 @@ binding name and two parentheses, just like we would for a named function.
 
 Let's compare syntax. The two are pretty close:
 
-```{rust,ignore}
-let add_one = |x: i32| -> i32 { 1 + x };
-fn  add_one   (x: i32) -> i32 { 1 + x }
+```{rust}
+let add_one = |&: x: i32| -> i32 { 1 + x };
+fn  add_one      (x: i32) -> i32 { 1 + x }
 ```
 
 As you may have noticed, closures infer their argument and return types, so you
@@ -4256,11 +4256,11 @@ There's one big difference between a closure and named functions, and it's in
 the name: a closure "closes over its environment." What does that mean? It means
 this:
 
-```{rust,ignore}
+```{rust}
 fn main() {
-    let x = 5;
+    let x: i32 = 5;
 
-    let printer = || { println!("x is: {}", x); };
+    let printer = |&:| { println!("x is: {}", x); };
 
     printer(); // prints "x is: 5"
 }
@@ -4276,7 +4276,7 @@ defined. The closure borrows any variables it uses, so this will error:
 fn main() {
     let mut x = 5;
 
-    let printer = || { println!("x is: {}", x); };
+    let printer = |&:| { println!("x is: {}", x); };
 
     x = 6; // error: cannot assign to `x` because it is borrowed
 }
@@ -4297,30 +4297,30 @@ now. We'll talk about them more in the "Threads" section of the guide.
 
 Closures are most useful as an argument to another function. Here's an example:
 
-```{rust,ignore}
-fn twice(x: i32, f: |i32| -> i32) -> i32 {
+```{rust}
+fn twice<F: Fn(i32) -> i32>(x: i32, f: F) -> i32 {
     f(x) + f(x)
 }
 
 fn main() {
-    let square = |x: i32| { x * x };
+    let square = |&: x: i32| { x * x };
 
     twice(5, square); // evaluates to 50
 }
 ```
 
 Let's break the example down, starting with `main`:
 
-```{rust,ignore}
-let square = |x: i32| { x * x };
+```{rust}
+let square = |&: x: i32| { x * x };
 ```
 
 We've seen this before. We make a closure that takes an integer, and returns
 its square.
 
-```{rust,ignore}
-# fn twice(x: i32, f: |i32| -> i32) -> i32 { f(x) + f(x) }
-# let square = |x: i32| { x * x };
+```{rust}
+# fn twice<F: Fn(i32) -> i32>(x: i32, f: F) -> i32 { f(x) + f(x) }
+# let square = |&: x: i32| { x * x };
 twice(5, square); // evaluates to 50
 ```
 
@@ -4342,9 +4342,9 @@ though, and that function takes an `i32` and returns an `i32`. Notice
 how the `|i32| -> i32` syntax looks a lot like our definition of `square`
 above, if we added the return type in:
 
-```{rust,ignore}
-let square = |x: i32| -> i32 { x * x };
-//           |i32|    -> i32
+```{rust}
+let square = |&: x: i32| -> i32 { x * x };
+//           |i32|       -> i32
 ```
 
 This function takes an `i32` and returns an `i32`.
@@ -4357,8 +4357,8 @@ Finally, `twice` returns an `i32` as well.
 
 Okay, let's look at the body of `twice`:
 
-```{rust,ignore}
-fn twice(x: i32, f: |i32| -> i32) -> i32 {
+```{rust}
+fn twice<F: Fn(i32) -> i32>(x: i32, f: F) -> i32 {
   f(x) + f(x)
 }
 ```
@@ -4375,8 +4375,8 @@ this technique a lot.
 If we didn't want to give `square` a name, we could just define it inline.
 This example is the same as the previous one:
 
-```{rust,ignore}
-fn twice(x: i32, f: |i32| -> i32) -> i32 {
+```{rust}
+fn twice<F: Fn(i32) -> i32>(x: i32, f: F) -> i32 {
     f(x) + f(x)
 }
 
@@ -4388,8 +4388,8 @@ fn main() {
 A named function's name can be used wherever you'd use a closure. Another
 way of writing the previous example:
 
-```{rust,ignore}
-fn twice(x: i32, f: |i32| -> i32) -> i32 {
+```{rust}
+fn twice<F: Fn(i32) -> i32>(x: i32, f: F) -> i32 {
     f(x) + f(x)
 }
 

src/doc/reference.md

@@ -1559,11 +1559,11 @@ Type parameters can be specified for a trait to make it generic. These appear
 after the trait name, using the same syntax used in [generic
 functions](#generic-functions).
 
-``` ignore
+```
 trait Seq<T> {
    fn len(&self) -> uint;
    fn elt_at(&self, n: uint) -> T;
-   fn iter(&self, |T|);
+   fn iter<F>(&self, F) where F: Fn(T);
 }
 ```
 
@@ -3217,8 +3217,8 @@ expression's captured environment.
 In this example, we define a function `ten_times` that takes a higher-order
 function argument, and call it with a lambda expression as an argument.
 
-``` ignore
-fn ten_times(f: |int|) {
+```
+fn ten_times<F>(f: F) where F: Fn(int) {
     let mut i = 0;
     while i < 10 {
         f(i);
@@ -3821,14 +3821,14 @@ or `extern`), a sequence of input types and an output type.
 
 An example of a `fn` type:
 
-``` ignore
+```
 fn add(x: int, y: int) -> int {
   return x + y;
 }
 
 let mut x = add(5,7);
 
-type Binop<'a> = |int,int|: 'a -> int;
+type Binop = fn(int, int) -> int;
 let bo: Binop = add;
 x = bo(5,7);
 ```
@@ -3849,17 +3849,17 @@ The type of a closure mapping an input of type `A` to an output of type `B` is
 
 An example of creating and calling a closure:
 
-``` ignore
+```rust
 let captured_var = 10i;
 
-let closure_no_args = || println!("captured_var={}", captured_var);
+let closure_no_args = |&:| println!("captured_var={}", captured_var);
 
-let closure_args = |arg: int| -> int {
+let closure_args = |&: arg: int| -> int {
   println!("captured_var={}, arg={}", captured_var, arg);
   arg // Note lack of semicolon after 'arg'
 };
 
-fn call_closure(c1: ||, c2: |int| -> int) {
+fn call_closure<F: Fn(), G: Fn(int) -> int>(c1: F, c2: G) {
   c1();
   c2(2);
 }