Rollup merge of #34125 - MichaelNecio:book_addition, r=steveklabnik

Noted that shadowing never destroys a value

Fixes issue #33887

r? @steveklabnik
This commit is contained in:
Steve Klabnik 2016-06-07 10:43:58 -04:00
commit 3ff22ccd40

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@ -241,7 +241,10 @@ println!("{}", x); // Prints "42"
Shadowing and mutable bindings may appear as two sides of the same coin, but
they are two distinct concepts that can't always be used interchangeably. For
one, shadowing enables us to rebind a name to a value of a different type. It
is also possible to change the mutability of a binding.
is also possible to change the mutability of a binding. Note that shadowing a
name does not alter or destroy the value it was bound to, and the value will
continue to exist until it goes out of scope, even if it is no longer accessible
by any means.
```rust
let mut x: i32 = 1;