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Edit aliasing section #178

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14 changes: 7 additions & 7 deletions reference/src/glossary.md
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Expand Up @@ -2,16 +2,17 @@

#### Aliasing

(Please note: a full aliasing model for Rust has not yet been constructed, but
at the moment we can give the following definition. The most developed potential
aliasing model so far is known as "Stacked Borrows", and can be found
[here](https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md).)

*Aliasing* is any time one pointer or reference points to a "span" of memory
*Aliasing* occurs when one pointer or reference points to a "span" of memory
that overlaps with the span of another pointer or reference. A span of memory is
similar to how a slice works: there's a base byte address as well as a length in
bytes.

**Note**: a full aliasing model for Rust, defining when aliasing is allowed
and when not, has not yet been defined. The purpose of this definition is to
define when aliasing *happens*, not when it is *allowed*. The most developed
potential aliasing model so far is known as "Stacked Borrows", and can be found
[here](https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md).

Consider the following example:

```rust
Expand All @@ -33,7 +34,6 @@ byte of `u` and `tail` points to the other seven bytes of `u` after it. Both `he
and `tail` alias `s`, any overlap is sufficient to count as an alias.

The span of a pointer or reference is the size of the value being pointed to or referenced.

Depending on the type, you can determine the size as follows:

* For a type `T` that is [`Sized`](https://doc.rust-lang.org/core/marker/trait.Sized.html)
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