Crate sinktools 

Extra Sink adaptors and functions.

Forward building with SinkBuild

For an intuitive API that matches the data flow direction, use SinkBuilder and the SinkBuild trait to chain adaptors in forward order:

use sinktools::{SinkBuilder, SinkBuild};
use sinktools::sink::SinkExt; // `futures::sink::SinkExt` for `.send(_).await`

// Forward chain: flatten -> filter_map -> map -> filter -> for_each
let mut pipeline = SinkBuilder::<Vec<i32>>::new()
    .flatten::<Vec<i32>>()          // Flatten input vectors
    .filter_map(|x: i32| {          // Double evens, filter odds
        if x % 2 == 0 {
            Some(x * 2)
        } else {
            None
        }
    })
    .map(|x| x + 1)                 // Add 1
    .filter(|x| *x < 100)           // Only values < 100
    .for_each(|x: i32| {            // Terminal operation
        println!("Received: {}", x);
    });

// Send nested data
pipeline.send(vec![1, 2, 3, 4]).await.unwrap();
pipeline.send(vec![5, 6]).await.unwrap();
pipeline.send(vec![]).await.unwrap();
pipeline.send(vec![7, 8, 9]).await.unwrap();

Direct construction

Alternatively, you can construct sink adaptors directly using their new methods:

use sinktools::{for_each, filter, map, filter_map, flatten};
use sinktools::sink::SinkExt; // for `.send(_).await`

// Build the same chain from inside out: sink <- filter <- map <- filter_map <- flatten
let sink = for_each(|x: i32| {
    println!("Received: {}", x);
});
let filter_sink = filter(|x: &i32| *x < 100, sink);
let map_sink = map(|x: i32| x + 1, filter_sink);
let filter_map_sink = filter_map(|x: i32| {
    if x % 2 == 0 {
        Some(x * 2)
    } else {
        None
    }
}, map_sink);
let mut complex_sink = flatten::<Vec<i32>, _>(filter_map_sink);

// Send nested data
complex_sink.send(vec![1, 2, 3, 4]).await.unwrap();
complex_sink.send(vec![5, 6]).await.unwrap();
complex_sink.send(vec![]).await.unwrap();
complex_sink.send(vec![7, 8, 9]).await.unwrap();

Each adaptor also provides a new_sink method which ensures the construction is correct for Sink to be implemented, but may require additional type arguments to aid inference.

The forward SinkBuilder API is more intuitive for direct users, as it matches the data flow direction. Direct construction is better for generated code as it aids compiler type inference.

Re-exports

pub use demux_map::demux_map;std

pub use demux_map_lazy::demux_map_lazy;std

pub use demux_var::SinkVariadic;variadics

pub use demux_var::demux_var;variadics

pub use variadics;variadics

Modules

demux_mapstd

DemuxMap and related items.

demux_map_lazystd

LazyDemuxSink and related items.

demux_varvariadics

DemuxVar and [variadics] for Sink.

filter

Filter and related items.

filter_map

FilterMap and related items.

flat_map

FlatMap and related items.

flatten

Flatten and related items.

for_each

ForEach consuming sink.

inspect

Inspect and related items.

lazy

LazySink, LazySource, and related items.

lazy_sink_source

LazySinkSource, and related items.

map

Map and related items.

send_iter

SendIter and related items.

send_stream

SendStream and related items.

sink

Asynchronous sinks.

try_for_each

TryForEach consuming sink.

unzip

Unzip.

Structs

SinkBuilder

Start a SinkBuild adaptor chain, with Item as the input item type.

Traits

Sink

A Sink is a value into which other values can be sent, asynchronously.

SinkBuild

A helper trait for building Sinks in forward order, unlike with Sinktools.

ToSinkBuild

Blanket trait for sending items from Self into a SinkBuild.

Functions

filter

Creates a Filter sink that filters items based on a predicate.

filter_map

Creates a FilterMap sink that filters and maps items in one step.

flat_map

Creates a FlatMap sink that maps each item to an iterator and flattens the results.

flatten

Creates a Flatten sink that flattens items that are iterators.

for_each

Creates a ForEach sink that consumes each item with a function.

inspect

Creates an Inspect sink that inspects each item without modifying it.

map

Creates a Map sink that applies a function to each item.

send_iter

Creates a SendIter future that sends all items from an iterator to a sink.

send_stream

Creates a SendStream future that sends all items from a stream to a sink.

try_for_each

Creates a TryForEach sink that consumes each item with a fallible function.

unzip

Creates an Unzip sink that splits tuple items into two separate sinks.