Rollup of 6 pull requests

src/doc/book/error-handling.md

@@ -2019,6 +2019,16 @@ impl Error for CliError {
             CliError::NotFound => "not found",
         }
     }
+
+    fn cause(&self) -> Option<&error::Error> {
+        match *self {            
+            CliError::Io(ref err) => Some(err),
+            CliError::Parse(ref err) => Some(err),
+            // Our custom error doesn't have an underlying cause, but we could
+            // modify it so that it does.
+            CliError::NotFound() => None,
+        }
+    }
 }
 ```
 

src/doc/book/match.md

@@ -36,10 +36,10 @@ give us an error:
 error: non-exhaustive patterns: `_` not covered
 ```
 
-Rust is telling us that we forgot a value. The compiler infers from `x` that it
-can have any positive 32bit value; for example 1 to 2,147,483,647. The `_` acts 
+Rust is telling us that we forgot some value. The compiler infers from `x` that it
+can have any 32bit integer value; for example -2,147,483,648 to 2,147,483,647. The `_` acts 
 as a 'catch-all', and will catch all possible values that *aren't* specified in 
-an arm of `match`. As you can see with the previous example, we provide `match` 
+an arm of `match`. As you can see in the previous example, we provide `match` 
 arms for integers 1-5, if `x` is 6 or any other value, then it is caught by `_`.
 
 `match` is also an expression, which means we can use it on the right-hand

src/doc/book/primitive-types.md

@@ -7,7 +7,7 @@ of these ones, as well, but these are the most primitive.
 
 # Booleans
 
-Rust has a built in boolean type, named `bool`. It has two values, `true` and `false`:
+Rust has a built-in boolean type, named `bool`. It has two values, `true` and `false`:
 
 ```rust
 let x = true;
@@ -89,13 +89,13 @@ Unsigned types use a `u` for their category, and signed types use `i`. The `i`
 is for ‘integer’. So `u8` is an eight-bit unsigned number, and `i8` is an
 eight-bit signed number.
 
-## Fixed size types
+## Fixed-size types
 
-Fixed size types have a specific number of bits in their representation. Valid
+Fixed-size types have a specific number of bits in their representation. Valid
 bit sizes are `8`, `16`, `32`, and `64`. So, `u32` is an unsigned, 32-bit integer,
 and `i64` is a signed, 64-bit integer.
 
-## Variable sized types
+## Variable-size types
 
 Rust also provides types whose size depends on the size of a pointer of the
 underlying machine. These types have ‘size’ as the category, and come in signed

src/doc/book/references-and-borrowing.md

@@ -212,7 +212,7 @@ fn main() {
 
 In other words, the mutable borrow is held through the rest of our example. What
 we want is for the mutable borrow by `y` to end so that the resource can be
-returned to the owner, `x`. `x` can then provide a mutable borrow to `println!`.
+returned to the owner, `x`. `x` can then provide a immutable borrow to `println!`.
 In Rust, borrowing is tied to the scope that the borrow is valid for. And our
 scopes look like this:
 

src/libcore/cmp.rs

@@ -14,6 +14,21 @@
 //! by the compiler to implement comparison operators. Rust programs may
 //! implement `PartialOrd` to overload the `<`, `<=`, `>`, and `>=` operators,
 //! and may implement `PartialEq` to overload the `==` and `!=` operators.
+//!
+//! # Examples
+//!
+//! ```
+//! let x: u32 = 0;
+//! let y: u32 = 1;
+//!
+//! // these two lines are equivalent
+//! assert_eq!(x < y, true);
+//! assert_eq!(x.lt(&y), true);
+//!
+//! // these two lines are also equivalent
+//! assert_eq!(x == y, false);
+//! assert_eq!(x.eq(&y), false);
+//! ```
 
 #![stable(feature = "rust1", since = "1.0.0")]
 
@@ -44,6 +59,16 @@ use option::Option::{self, Some};
 /// only if `a != b`.
 ///
 /// This trait can be used with `#[derive]`.
+///
+/// # Examples
+///
+/// ```
+/// let x: u32 = 0;
+/// let y: u32 = 1;
+///
+/// assert_eq!(x == y, false);
+/// assert_eq!(x.eq(&y), false);
+/// ```
 #[lang = "eq"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait PartialEq<Rhs: ?Sized = Self> {
@@ -226,6 +251,16 @@ impl PartialOrd for Ordering {
 ///
 /// This trait can be used with `#[derive]`. When `derive`d, it will produce an ordering
 /// based on the top-to-bottom declaration order of the struct's members.
+///
+/// # Examples
+///
+/// ```
+/// let x : u32 = 0;
+/// let y : u32 = 1;
+///
+/// assert_eq!(x < y, true);
+/// assert_eq!(x.lt(&y), true);
+/// ```
 #[lang = "ord"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> {

src/librustc_typeck/diagnostics.rs

@@ -3167,8 +3167,8 @@ x <<= 2;
 To fix this error, please check that this type implements this binary
 operation. Example:
 
-```compile_fail
-let x = 12u32; // the `u32` type does implement the `ShlAssign` trait
+```
+let mut x = 12u32; // the `u32` type does implement the `ShlAssign` trait
 
 x <<= 2; // ok!
 ```