mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

update the iterator tutorial

Browse Source
This commit is contained in:
Daniel Micay 2013-08-13 00:37:50 -04:00
parent af9ddd7563
commit 6a21f22767
1 changed files with 11 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
doc/tutorial-container.md
View File

@ -112,10 +112,10 @@ iterator object. For example, vector slices several iterators available:
* `iter()` and `rev_iter()`, for immutable references to the elements * `iter()` and `rev_iter()`, for immutable references to the elements
* `mut_iter()` and `mut_rev_iter()`, for mutable references to the elements * `mut_iter()` and `mut_rev_iter()`, for mutable references to the elements
* `consume_iter()` and `consume_rev_iter`, to move the elements out by-value * `move_iter()` and `move_rev_iter`, to move the elements out by-value
A typical mutable container will implement at least `iter()`, `mut_iter()` and A typical mutable container will implement at least `iter()`, `mut_iter()` and
`consume_iter()` along with the reverse variants if it maintains an order. `move_iter()` along with the reverse variants if it maintains an order.
### Freezing ### Freezing
@ -139,9 +139,9 @@ and `&mut`.
## Iterator adaptors ## Iterator adaptors
The `IteratorUtil` trait implements common algorithms as methods extending The `Iterator` trait provides many common algorithms as default methods. For
every `Iterator` implementation. For example, the `fold` method will accumulate example, the `fold` method will accumulate the items yielded by an `Iterator`
the items yielded by an `Iterator` into a single value: into a single value:
~~~ ~~~
let xs = [1, 9, 2, 3, 14, 12]; let xs = [1, 9, 2, 3, 14, 12];
@ -154,14 +154,10 @@ Some adaptors return an adaptor object implementing the `Iterator` trait itself:
~~~ ~~~
let xs = [1, 9, 2, 3, 14, 12]; let xs = [1, 9, 2, 3, 14, 12];
let ys = [5, 2, 1, 8]; let ys = [5, 2, 1, 8];
let sum = xs.iter().chain_(ys.iter()).fold(0, |a, b| a + *b); let sum = xs.iter().chain(ys.iter()).fold(0, |a, b| a + *b);
assert_eq!(sum, 57); assert_eq!(sum, 57);
~~~ ~~~
Note that some adaptors like the `chain_` method above use a trailing
underscore to work around an issue with method resolve. The underscores will be
dropped when they become unnecessary.
## For loops ## For loops
The `for` keyword can be used as sugar for iterating through any iterator: The `for` keyword can be used as sugar for iterating through any iterator:
@ -212,7 +208,7 @@ Iterators offer generic conversion to containers with the `collect` adaptor:
~~~ ~~~
let xs = [0, 1, 1, 2, 3, 5, 8]; let xs = [0, 1, 1, 2, 3, 5, 8];
let ys = xs.rev_iter().skip(1).transform(|&x| x * 2).collect::<~[int]>(); let ys = xs.rev_iter().skip(1).map(|&x| x * 2).collect::<~[int]>();
assert_eq!(ys, ~[10, 6, 4, 2, 2, 0]); assert_eq!(ys, ~[10, 6, 4, 2, 2, 0]);
~~~ ~~~
@ -307,13 +303,13 @@ for &x in it.invert() {
The `rev_iter` and `mut_rev_iter` methods on vectors just return an inverted The `rev_iter` and `mut_rev_iter` methods on vectors just return an inverted
version of the standard immutable and mutable vector iterators. version of the standard immutable and mutable vector iterators.
The `chain_`, `transform`, `filter`, `filter_map` and `peek` adaptors are The `chain`, `map`, `filter`, `filter_map` and `inspect` adaptors are
`DoubleEndedIterator` implementations if the underlying iterators are. `DoubleEndedIterator` implementations if the underlying iterators are.
~~~ ~~~
let xs = [1, 2, 3, 4]; let xs = [1, 2, 3, 4];
let ys = [5, 6, 7, 8]; let ys = [5, 6, 7, 8];
let mut it = xs.iter().chain_(ys.iter()).transform(|&x| x * 2); let mut it = xs.iter().chain(ys.iter()).map(|&x| x * 2);
printfln!("%?", it.next()); // prints `Some(2)` printfln!("%?", it.next()); // prints `Some(2)`
@ -329,13 +325,13 @@ The `RandomAccessIterator` trait represents an iterator offering random access
to the whole range. The `indexable` method retrieves the number of elements to the whole range. The `indexable` method retrieves the number of elements
accessible with the `idx` method. accessible with the `idx` method.
The `chain_` adaptor is an implementation of `RandomAccessIterator` if the The `chain` adaptor is an implementation of `RandomAccessIterator` if the
underlying iterators are. underlying iterators are.
~~~ ~~~
let xs = [1, 2, 3, 4, 5]; let xs = [1, 2, 3, 4, 5];
let ys = ~[7, 9, 11]; let ys = ~[7, 9, 11];
let mut it = xs.iter().chain_(ys.iter()); let mut it = xs.iter().chain(ys.iter());
printfln!("%?", it.idx(0)); // prints `Some(&1)` printfln!("%?", it.idx(0)); // prints `Some(&1)`
printfln!("%?", it.idx(5)); // prints `Some(&7)` printfln!("%?", it.idx(5)); // prints `Some(&7)`
printfln!("%?", it.idx(7)); // prints `Some(&11)` printfln!("%?", it.idx(7)); // prints `Some(&11)`