Struct fringe::generator::Generator
[−]
[src]
pub struct Generator<Input: Send, Output: Send, Stack: Stack> { // some fields omitted }
Generator wraps a function and allows suspending its execution more than once, returning a value each time.
The first time resume(input0)
is called, the function is called as f(yielder, input0)
.
It runs until it suspends its execution through yielder.suspend(output0)
, after which
resume(input0)
returns output0
. The function can be resumed again using resume(input1)
,
after which yielder.suspend(output0)
returns input1
, and so on. Once the function returns,
the resume()
call will return None
, and it will return None
every time it is called
after that.
If the generator function panics, the panic is propagated through the resume()
call as usual.
After the generator function returns or panics, it is safe to reclaim the generator stack
using unwrap()
.
state()
can be used to determine whether the generator function has returned;
the state is State::Runnable
after creation and suspension, and State::Unavailable
once the generator function returns or panics.
When the input type is ()
, a generator implements the Iterator trait.
Example
use fringe::{OsStack, Generator}; let stack = OsStack::new(0).unwrap(); let mut add_one = Generator::new(stack, move |yielder, mut input| { loop { if input == 0 { break } input = yielder.suspend(input + 1) } }); println!("{:?}", add_one.resume(2)); // prints Some(3) println!("{:?}", add_one.resume(3)); // prints Some(4) println!("{:?}", add_one.resume(0)); // prints None
Iterator example
use fringe::{OsStack, Generator}; let stack = OsStack::new(0).unwrap(); let mut nat = Generator::new(stack, move |yielder, ()| { for i in 1.. { yielder.suspend(i) } }); println!("{:?}", nat.next()); // prints Some(0) println!("{:?}", nat.next()); // prints Some(1) println!("{:?}", nat.next()); // prints Some(2)
Methods
impl<Input, Output, Stack> Generator<Input, Output, Stack> where Input: Send, Output: Send, Stack: Stack
[src]
fn new<F>(stack: Stack, f: F) -> Generator<Input, Output, Stack> where Stack: GuardedStack, F: FnOnce(&mut Yielder<Input, Output, Stack>, Input) + Send
Creates a new generator.
unsafe fn unsafe_new<F>(stack: Stack, f: F) -> Generator<Input, Output, Stack> where F: FnOnce(&mut Yielder<Input, Output, Stack>, Input) + Send
Same as new
, but does not require stack
to have a guard page.
This function is unsafe because the generator function can easily violate memory safety by overflowing the stack. It is useful in environments where guarded stacks do not exist, e.g. in absence of an MMU.
fn resume(&mut self, input: Input) -> Option<Output>
Resumes the generator and return the next value it yields.
If the generator function has returned, returns None
.
fn state(&self) -> State
Returns the state of the generator.
fn unwrap(self) -> Stack
Extracts the stack from a generator when the generator function has returned.
If the generator function has not returned
(i.e. self.state() == State::Runnable
), panics.
Trait Implementations
impl<Input: Debug + Send, Output: Debug + Send, Stack: Debug + Stack> Debug for Generator<Input, Output, Stack>
[src]
impl<Output, Stack> Iterator for Generator<(), Output, Stack> where Output: Send, Stack: Stack
[src]
type Item = Output
The type of the elements being iterated over.
fn next(&mut self) -> Option<Self::Item>
Advances the iterator and returns the next value. Read more
fn size_hint(&self) -> (usize, Option<usize>)
1.0.0
Returns the bounds on the remaining length of the iterator. Read more
fn count(self) -> usize
1.0.0
Consumes the iterator, counting the number of iterations and returning it. Read more
fn last(self) -> Option<Self::Item>
1.0.0
Consumes the iterator, returning the last element. Read more
fn nth(&mut self, n: usize) -> Option<Self::Item>
1.0.0
Consumes the n
first elements of the iterator, then returns the next()
one. Read more
fn chain<U>(self, other: U) -> Chain<Self, U::IntoIter> where U: IntoIterator<Item=Self::Item>
1.0.0
Takes two iterators and creates a new iterator over both in sequence. Read more
fn zip<U>(self, other: U) -> Zip<Self, U::IntoIter> where U: IntoIterator
1.0.0
'Zips up' two iterators into a single iterator of pairs. Read more
fn map<B, F>(self, f: F) -> Map<Self, F> where F: FnMut(Self::Item) -> B
1.0.0
Takes a closure and creates an iterator which calls that closure on each element. Read more
fn filter<P>(self, predicate: P) -> Filter<Self, P> where P: FnMut(&Self::Item) -> bool
1.0.0
Creates an iterator which uses a closure to determine if an element should be yielded. Read more
fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> where F: FnMut(Self::Item) -> Option<B>
1.0.0
Creates an iterator that both filters and maps. Read more
fn enumerate(self) -> Enumerate<Self>
1.0.0
Creates an iterator which gives the current iteration count as well as the next value. Read more
fn peekable(self) -> Peekable<Self>
1.0.0
Creates an iterator which can use peek
to look at the next element of the iterator without consuming it. Read more
fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where P: FnMut(&Self::Item) -> bool
1.0.0
Creates an iterator that [skip()
]s elements based on a predicate. Read more
fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> where P: FnMut(&Self::Item) -> bool
1.0.0
Creates an iterator that yields elements based on a predicate. Read more
fn skip(self, n: usize) -> Skip<Self>
1.0.0
Creates an iterator that skips the first n
elements. Read more
fn take(self, n: usize) -> Take<Self>
1.0.0
Creates an iterator that yields its first n
elements. Read more
fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where F: FnMut(&mut St, Self::Item) -> Option<B>
1.0.0
An iterator adaptor similar to [fold()
] that holds internal state and produces a new iterator. Read more
fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where F: FnMut(Self::Item) -> U, U: IntoIterator
1.0.0
Creates an iterator that works like map, but flattens nested structure. Read more
fn fuse(self) -> Fuse<Self>
1.0.0
Creates an iterator which ends after the first None
. Read more
fn inspect<F>(self, f: F) -> Inspect<Self, F> where F: FnMut(&Self::Item) -> ()
1.0.0
Do something with each element of an iterator, passing the value on. Read more
fn by_ref(&mut self) -> &mut Self
1.0.0
Borrows an iterator, rather than consuming it. Read more
fn collect<B>(self) -> B where B: FromIterator<Self::Item>
1.0.0
Transforms an iterator into a collection. Read more
fn partition<B, F>(self, f: F) -> (B, B) where B: Default + Extend<Self::Item>, F: FnMut(&Self::Item) -> bool
1.0.0
Consumes an iterator, creating two collections from it. Read more
fn fold<B, F>(self, init: B, f: F) -> B where F: FnMut(B, Self::Item) -> B
1.0.0
An iterator adaptor that applies a function, producing a single, final value. Read more
fn all<F>(&mut self, f: F) -> bool where F: FnMut(Self::Item) -> bool
1.0.0
Tests if every element of the iterator matches a predicate. Read more
fn any<F>(&mut self, f: F) -> bool where F: FnMut(Self::Item) -> bool
1.0.0
Tests if any element of the iterator matches a predicate. Read more
fn find<P>(&mut self, predicate: P) -> Option<Self::Item> where P: FnMut(&Self::Item) -> bool
1.0.0
Searches for an element of an iterator that satisfies a predicate. Read more
fn position<P>(&mut self, predicate: P) -> Option<usize> where P: FnMut(Self::Item) -> bool
1.0.0
Searches for an element in an iterator, returning its index. Read more
fn rposition<P>(&mut self, predicate: P) -> Option<usize> where P: FnMut(Self::Item) -> bool, Self: ExactSizeIterator + DoubleEndedIterator
1.0.0
Searches for an element in an iterator from the right, returning its index. Read more
fn max(self) -> Option<Self::Item> where Self::Item: Ord
1.0.0
Returns the maximum element of an iterator. Read more
fn min(self) -> Option<Self::Item> where Self::Item: Ord
1.0.0
Returns the minimum element of an iterator. Read more
fn max_by_key<B, F>(self, f: F) -> Option<Self::Item> where B: Ord, F: FnMut(&Self::Item) -> B
1.6.0
Returns the element that gives the maximum value from the specified function. Read more
fn min_by_key<B, F>(self, f: F) -> Option<Self::Item> where B: Ord, F: FnMut(&Self::Item) -> B
1.6.0
Returns the element that gives the minimum value from the specified function. Read more
fn rev(self) -> Rev<Self> where Self: DoubleEndedIterator
1.0.0
Reverses an iterator's direction. Read more
fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB) where FromA: Default + Extend<A>, FromB: Default + Extend<B>, Self: Iterator<Item=(A, B)>
1.0.0
Converts an iterator of pairs into a pair of containers. Read more
fn cloned<'a, T>(self) -> Cloned<Self> where Self: Iterator<Item=&'a T>, T: 'a + Clone
1.0.0
Creates an iterator which clone()
s all of its elements. Read more
fn cycle(self) -> Cycle<Self> where Self: Clone
1.0.0
Repeats an iterator endlessly. Read more
fn sum<S>(self) -> S where S: Sum<Self::Item>
1.11.0
Sums the elements of an iterator. Read more
fn product<P>(self) -> P where P: Product<Self::Item>
1.11.0
Iterates over the entire iterator, multiplying all the elements Read more
fn cmp<I>(self, other: I) -> Ordering where I: IntoIterator<Item=Self::Item>, Self::Item: Ord
1.5.0
Lexicographically compares the elements of this Iterator
with those of another. Read more
fn partial_cmp<I>(self, other: I) -> Option<Ordering> where I: IntoIterator, Self::Item: PartialOrd<I::Item>
1.5.0
Lexicographically compares the elements of this Iterator
with those of another. Read more
fn eq<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialEq<I::Item>
1.5.0
Determines if the elements of this Iterator
are equal to those of another. Read more
fn ne<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialEq<I::Item>
1.5.0
Determines if the elements of this Iterator
are unequal to those of another. Read more
fn lt<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>
1.5.0
Determines if the elements of this Iterator
are lexicographically less than those of another. Read more
fn le<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>
1.5.0
Determines if the elements of this Iterator
are lexicographically less or equal to those of another. Read more
fn gt<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>
1.5.0
Determines if the elements of this Iterator
are lexicographically greater than those of another. Read more
fn ge<I>(self, other: I) -> bool where I: IntoIterator, Self::Item: PartialOrd<I::Item>
1.5.0
Determines if the elements of this Iterator
are lexicographically greater than or equal to those of another. Read more