Enum plumbum::ConduitM

pub enum ConduitM<'a, I, O, A> {
    Pure(Box<A>),
    Defer(Kleisli<'a, (), I, O, A>),
    Await(Kleisli<'a, Option<I>, I, O, A>),
    Yield(Box<O>, Kleisli<'a, (), I, O, A>),
    Leftover(Box<I>, Kleisli<'a, (), I, O, A>),
}

Represents a conduit, i.e. a sequence of await/yield actions.

• I is the type of values the conduit consumes from upstream.
• O is the type of values the conduit passes downstream.
• A is the return type of the conduit.

Variants

Pure(Box<A>)

The case Pure(a) means that the conduit contains no further actions and just returns the result a.

Defer(Kleisli<'a, (), I, O, A>)

The case Defer(k) means that the conduit needs another iteration to make progress, and the remaining (suspended) program is given by the kleisli arrow k

Await(Kleisli<'a, Option<I>, I, O, A>)

The case Await(k) means that the conduit waits for a value of type I, and the remaining (suspended) program is given by the kleisli arrow k.

Yield(Box<O>, Kleisli<'a, (), I, O, A>)

The case Yield(o, k) means that the conduit yields a value of type O, and the remaining (suspended) program is given by the kleisli arrow k.

Leftover(Box<I>, Kleisli<'a, (), I, O, A>)

The case Leftover(i, k) means that the conduit has a leftover value of type I, and the remaining (suspended) program is given by the kleisli arrow k.

Methods

impl<'a, O> ConduitM<'a, (), O, ()>

fn to_producer<I>(self) -> ConduitM<'a, I, O, ()> where O: 'static

Generalize a Source by universally quantifying the input type.

fn connect<A>(self, sink: Sink<'a, O, A>) -> A where O: 'static

Pulls data from the source and pushes it into the sink.

Example

use std::iter::FromIterator;
use plumbum::{Source, Sink, produce};

let src = Source::from_iter(vec![42, 43]);
let sink = Sink::fold(0, |x, y| x + y);

assert_eq!(src.connect(sink), 85);

impl<'a, I, O> ConduitM<'a, I, O, ()>

fn fuse<P, A>(self, other: ConduitM<'a, O, P, A>) -> ConduitM<'a, I, P, A> where I: 'static, O: 'static, P: 'static, A: 'a

Combines two conduits together into a new conduit.

Example

use std::iter::FromIterator;
use plumbum::{Conduit, Source, Sink};

let src = Source::from_iter(vec![42, 43]);
let conduit = Conduit::transform(|x| 1 + x);
let sink = Sink::fold(0, |x, y| x + y);

assert_eq!(src.fuse(conduit).connect(sink), 87);

fn transform<F>(f: F) -> Self where F: 'a + Fn(I) -> O

Apply a transformation to all values in a stream.

impl<'a, I, A> ConduitM<'a, I, Void, A>

fn to_consumer<O>(self) -> ConduitM<'a, I, O, A>

Generalize a Sink by universally quantifying the output type.

fn fold<F>(a: A, f: F) -> Self where A: 'a, F: 'a + Fn(A, I) -> A

Fold all values from upstream into a final value.

impl<'a, I, O, A> ConduitM<'a, I, O, A>

fn and_then<B, F>(self, js: F) -> ConduitM<'a, I, O, B> where F: 'a + FnOnce(A) -> ConduitM<'a, I, O, B>

Appends a continuation to a conduit. Which means, given a function from A to ConduitM<I, O, B>, passes the return value of the conduit to the function, and returns the resulting program.

fn and<B: 'a>(self, other: ConduitM<'a, I, O, B>) -> ConduitM<'a, I, O, B> where I: 'a, O: 'a

Appends two conduits together, which means, it returns a new conduit that executes both conduits sequentially, and forwards the return value of the second.

fn zip<B: 'a>(self, other: ConduitM<'a, I, O, B>) -> ConduitM<'a, I, O, (A, B)> where A: 'a, I: 'a, O: 'a

Zips two conduits together, which means, it returns a new conduit that executes both conduits sequentially, and forwards both return values.

fn map<B, F>(self, f: F) -> ConduitM<'a, I, O, B> where F: 'a + FnOnce(A) -> B

Modifies the return value of the conduit. Seen differently, it lifts a function from A to B into a function from ConduitM<I, O, A> to ConduitM<I, O, B>.

Trait Implementations

impl<'a, I, O: 'a> FromIterator<O> for ConduitM<'a, I, O, ()>

fn from_iter<T: IntoIterator<Item=O>>(iterator: T) -> Self

Creates a value from an iterator.

impl<'a, I, O, A: PartialEq> PartialEq for ConduitM<'a, I, O, A>

fn eq(&self, other: &ConduitM<'a, I, O, A>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<'a, I, O, A: Debug> Debug for ConduitM<'a, I, O, A>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<'a, I, O, A> From<A> for ConduitM<'a, I, O, A>

fn from(a: A) -> ConduitM<'a, I, O, A>

Performs the conversion.