Callable



An extendable base class for callable classes, designed to work nicely with Flow.

Type definition:

``js
// @flow
declare class Callable extends Function {
// See https://github.com/facebook/flow/issues/3084
// (A): B
$call: A => B;
constructor(A => B): this;
}
`

Examples:

#### Extend Callable with custom methods
`js
// @flow
import Callable from "callable-class";

class Composable extends Callable {
andThen(next: B => C): Composable {
return new Composable(x => next(this(x)));
}
}

const foo = new Composable(x => [...x, 1])
.andThen(x => [...x, 2])
.andThen(x => [...x, 3]);

console.log(foo([])); // [1, 2, 3]
`

#### Extend Callable with custom fields and constructor
`js
// @flow
import Callable from "callable-class";

class ActionCreator extends Callable {
type: string;
constructor(type: Type, fn: A => B) {
super(fn);
this.type = type;
}
}

const foo = new ActionCreator("foo", x => x + 1);

console.log(foo.type); // "foo"
console.log(foo(0)); // 1
``