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25 changes: 22 additions & 3 deletions src/doc/guide-lifetimes.md
Original file line number Diff line number Diff line change
Expand Up @@ -559,9 +559,14 @@ points at a static constant).

# Named lifetimes

Let's look at named lifetimes in more detail. Named lifetimes allow
for grouping of parameters by lifetime. For example, consider this
function:
Lifetimes can be named and referenced. For example, the special lifetime
`'static`, which does not go out of scope, can be used to create global
variables and communicate between tasks (see the manual for usecases).

## Parameter Lifetimes

Named lifetimes allow for grouping of parameters by lifetime.
For example, consider this function:

~~~
# struct Point {x: f64, y: f64}; // as before
Expand Down Expand Up @@ -655,6 +660,20 @@ fn select<'r, T>(shape: &Shape, threshold: f64,

This is equivalent to the previous definition.

## Labeled Control Structures

Named lifetime notation can also be used to control the flow of execution:

~~~
'h: for i in range(0,10) {
'g: loop {
if i % 2 == 0 { continue 'h; }
if i == 9 { break 'h; }
break 'g;
}
}
~~~

# Conclusion

So there you have it: a (relatively) brief tour of the lifetime
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3 changes: 2 additions & 1 deletion src/doc/tutorial.md
Original file line number Diff line number Diff line change
Expand Up @@ -2103,7 +2103,8 @@ a `&T` pointer. `MutexArc` is an example of a *sharable* type with internal muta
These are types that do not contain any data whose lifetime is bound to
a particular stack frame. These are types that do not contain any
references, or types where the only contained references
have the `'static` lifetime.
have the `'static` lifetime. (For more on named lifetimes and their uses,
see the [references and lifetimes guide][lifetimes].)

> ***Note:*** These two traits were referred to as 'kinds' in earlier
> iterations of the language, and often still are.
Expand Down