effect-io-ai

Package: effect
Module: Channel

Channel.Channel

A Channel is a nexus of I/O operations, which supports both reading and writing. A channel may read values of type InElem and write values of type OutElem. When the channel finishes, it yields a value of type OutDone. A channel may fail with a value of type OutErr.

Details

Channels are the foundation of Streams: both streams and sinks are built on channels. Most users shouldn’t have to use channels directly, as streams and sinks are much more convenient and cover all common use cases. However, when adding new stream and sink operators, or doing something highly specialized, it may be useful to use channels directly.

Channels compose in a variety of ways:

• Piping: One channel can be piped to another channel, assuming the input type of the second is the same as the output type of the first.
• Sequencing: The terminal value of one channel can be used to create another channel, and both the first channel and the function that makes the second channel can be composed into a channel.
• Concatenating: The output of one channel can be used to create other channels, which are all concatenated together. The first channel and the function that makes the other channels can be composed into a channel.

Example (Typing channels)

import type { Channel } from "effect"

// A channel that outputs numbers and requires no environment
type NumberChannel = Channel.Channel<number>

// A channel that outputs strings, can fail with Error, completes with boolean
type StringChannel = Channel.Channel<string, Error, boolean>

// A channel with all type parameters specified
type FullChannel = Channel.Channel<
  string, // OutElem - output elements
  Error, // OutErr - output errors
  number, // OutDone - completion value
  number, // InElem - input elements
  string, // InErr - input errors
  boolean, // InDone - input completion
  { db: string } // Env - required environment
>

Signature

export interface Channel<
  out OutElem,
  out OutErr = never,
  out OutDone = void,
  in InElem = unknown,
  in InErr = unknown,
  in InDone = unknown,
  out Env = never
> extends Variance<OutElem, OutErr, OutDone, InElem, InErr, InDone, Env>, Pipeable {
  [Unify.typeSymbol]?: unknown
  [Unify.unifySymbol]?: ChannelUnify<this>
  [Unify.ignoreSymbol]?: ChannelUnifyIgnore
}

Source

Since v2.0.0