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Fixed one textual mistake and one casing error.
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Corrected "Ownership":

- [`Variable bindings`] link was not processed properly.
- Changed the paragraph about move semantics with two vectors, because it was confusing.
- Removed "So it may not be as inefficient as it initially seems", because there is nothing that seems inefficient in copying pointers only.
- Other text corrections.

Fixed copied-and-pasted text mistakes.

Revised the paragraph about moving a vector (taking into account suggestions by echochamber).

Fixed markdown.

Fixes requested by steveklabnik.

Brought back a sentence about supposed inefficiency.
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michal-czardybon committed May 11, 2015
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2 changes: 1 addition & 1 deletion src/doc/trpl/lifetimes.md
Original file line number Diff line number Diff line change
Expand Up @@ -5,7 +5,7 @@ Rust’s most unique and compelling features, with which Rust developers should
become quite acquainted. Ownership is how Rust achieves its largest goal,
memory safety. There are a few distinct concepts, each with its own chapter:

* [ownership][ownership], ownership, the key concept
* [ownership][ownership], the key concept
* [borrowing][borrowing], and their associated feature ‘references’
* lifetimes, which you’re reading now

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28 changes: 14 additions & 14 deletions src/doc/trpl/ownership.md
Original file line number Diff line number Diff line change
Expand Up @@ -6,7 +6,7 @@ become quite acquainted. Ownership is how Rust achieves its largest goal,
memory safety. There are a few distinct concepts, each with its own
chapter:

* ownership, which you’re reading now.
* ownership, which you’re reading now
* [borrowing][borrowing], and their associated feature ‘references’
* [lifetimes][lifetimes], an advanced concept of borrowing

Expand All @@ -23,7 +23,7 @@ Before we get to the details, two important notes about the ownership system.
Rust has a focus on safety and speed. It accomplishes these goals through many
‘zero-cost abstractions’, which means that in Rust, abstractions cost as little
as possible in order to make them work. The ownership system is a prime example
of a zero cost abstraction. All of the analysis we’ll talk about in this guide
of a zero-cost abstraction. All of the analysis we’ll talk about in this guide
is _done at compile time_. You do not pay any run-time cost for any of these
features.

Expand All @@ -41,7 +41,7 @@ With that in mind, let’s learn about ownership.

# Ownership

[`Variable bindings`][bindings] have a property in Rust: they ‘have ownership’
[Variable bindings][bindings] have a property in Rust: they ‘have ownership’
of what they’re bound to. This means that when a binding goes out of scope, the
resource that they’re bound to are freed. For example:

Expand Down Expand Up @@ -106,8 +106,8 @@ take(v);
println!("v[0] is: {}", v[0]);
```

Same error: use of moved value.” When we transfer ownership to something else,
we say that we’ve ‘moved’ the thing we refer to. You don’t need some sort of
Same error: use of moved value’. When we transfer ownership to something else,
we say that we’ve ‘moved’ the thing we refer to. You don’t need any sort of
special annotation here, it’s the default thing that Rust does.

## The details
Expand All @@ -121,19 +121,19 @@ let v = vec![1, 2, 3];
let v2 = v;
```

The first line creates some data for the vector on the [stack][sh], `v`. The
vector’s data, however, is stored on the [heap][sh], and so it contains a
pointer to that data. When we move `v` to `v2`, it creates a copy of that pointer,
for `v2`. Which would mean two pointers to the contents of the vector on the
heap. That would be a problem: it would violate Rust’s safety guarantees by
introducing a data race. Therefore, Rust forbids using `v` after we’ve done the
move.
The first line allocates memory for the vector object, `v`, and for the data it
contains. The vector object is stored on the [stack][sh] and contains a pointer
to the content (`[1, 2, 3]`) stored on the [heap][sh]. When we move `v` to `v2`,
it creates a copy of that pointer, for `v2`. Which means that there would be two
pointers to the content of the vector on the heap. It would violate Rust’s
safety guarantees by introducing a data race. Therefore, Rust forbids using `v`
after we’ve done the move.

[sh]: the-stack-and-the-heap.html

It’s also important to note that optimizations may remove the actual copy of
the bytes, depending on circumstances. So it may not be as inefficient as it
initially seems.
the bytes on the stack, depending on circumstances. So it may not be as
inefficient as it initially seems.

## `Copy` types

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4 changes: 2 additions & 2 deletions src/doc/trpl/references-and-borrowing.md
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Expand Up @@ -6,7 +6,7 @@ become quite acquainted. Ownership is how Rust achieves its largest goal,
memory safety. There are a few distinct concepts, each with its own
chapter:

* [ownership][ownership], ownership, the key concept
* [ownership][ownership], the key concept
* borrowing, which you’re reading now
* [lifetimes][lifetimes], an advanced concept of borrowing

Expand Down Expand Up @@ -368,4 +368,4 @@ statement 1 at 3:14
println!("{}", y);
}
```
```
2 changes: 1 addition & 1 deletion src/doc/trpl/while-loops.md
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@@ -1,4 +1,4 @@
% while loops
% while Loops

Rust also has a `while` loop. It looks like this:

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