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doc: updates rust manual (loop to continue) #14142

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doc: updates rust manual (loop to continue) #14142

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20 changes: 9 additions & 11 deletions src/doc/rust.md
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Original file line number Diff line number Diff line change
Expand Up @@ -208,7 +208,7 @@ The keywords are the following strings:
~~~~ {.notrust .keyword}
as
box break
crate
continue crate
else enum extern
false fn for
if impl in
Expand Down Expand Up @@ -2924,18 +2924,16 @@ while i < 10 {

### Infinite loops

The keyword `loop` in Rust appears both in _loop expressions_ and in _continue expressions_.
A loop expression denotes an infinite loop;
see [Continue expressions](#continue-expressions) for continue expressions.
A `loop` expression denotes an infinite loop.

~~~~ {.notrust .ebnf .gram}
loop_expr : [ lifetime ':' ] "loop" '{' block '}';
~~~~

A `loop` expression may optionally have a _label_.
If a label is present,
then labeled `break` and `loop` expressions nested within this loop may exit out of this loop or return control to its head.
See [Break expressions](#break-expressions).
then labeled `break` and `continue` expressions nested within this loop may exit out of this loop or return control to its head.
See [Break expressions](#break-expressions) and [Continue expressions](#continue-expressions).

### Break expressions

Expand All @@ -2953,21 +2951,21 @@ but must enclose it.
### Continue expressions

~~~~ {.notrust .ebnf .gram}
continue_expr : "loop" [ lifetime ];
continue_expr : "continue" [ lifetime ];
~~~~

A continue expression, written `loop`, also has an optional `label`.
A `continue` expression has an optional `label`.
If the label is absent,
then executing a `loop` expression immediately terminates the current iteration of the innermost loop enclosing it,
then executing a `continue` expression immediately terminates the current iteration of the innermost loop enclosing it,
returning control to the loop *head*.
In the case of a `while` loop,
the head is the conditional expression controlling the loop.
In the case of a `for` loop, the head is the call-expression controlling the loop.
If the label is present, then `loop foo` returns control to the head of the loop with label `foo`,
If the label is present, then `continue foo` returns control to the head of the loop with label `foo`,
which need not be the innermost label enclosing the `break` expression,
but must enclose it.

A `loop` expression is only permitted in the body of a loop.
A `continue` expression is only permitted in the body of a loop.

### For expressions

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