<B>(that: Iterable<B>): <A>(self: Iterable<A>) => Iterable<A | B>
<A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>Prepends the specified prefix iterable to the beginning of the specified iterable.
Example (Prepending another iterable)
import { Iterable } from "effect"
import * as assert from "node:assert"
assert.deepStrictEqual(
Array.from(Iterable.prependAll([1, 2], ["a", "b"])),
["a", "b", 1, 2]
)combining
Source effect/Iterable.ts:2447 lines
export const const prependAll: {
<B>(that: Iterable<B>): <A>(
self: Iterable<A>
) => Iterable<A | B>
<A, B>(
self: Iterable<A>,
that: Iterable<B>
): Iterable<A | B>
}
Prepends the specified prefix iterable to the beginning of the specified iterable.
Example (Prepending another iterable)
import { Iterable } from "effect"
import * as assert from "node:assert"
assert.deepStrictEqual(
Array.from(Iterable.prependAll([1, 2], ["a", "b"])),
["a", "b", 1, 2]
)
prependAll: {
<function (type parameter) B in <B>(that: Iterable<B>): <A>(self: Iterable<A>) => Iterable<A | B>B>(that: Iterable<B>that: interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) B in <B>(that: Iterable<B>): <A>(self: Iterable<A>) => Iterable<A | B>B>): <function (type parameter) A in <A>(self: Iterable<A>): Iterable<A | B>A>(self: Iterable<A>self: interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) A in <A>(self: Iterable<A>): Iterable<A | B>A>) => interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) A in <A>(self: Iterable<A>): Iterable<A | B>A | function (type parameter) B in <B>(that: Iterable<B>): <A>(self: Iterable<A>) => Iterable<A | B>B>
<function (type parameter) A in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>A, function (type parameter) B in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>B>(self: Iterable<A>self: interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) A in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>A>, that: Iterable<B>that: interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) B in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>B>): interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) A in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>A | function (type parameter) B in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>B>
} = dual<(...args: Array<any>) => any, <A, B>(self: Iterable<A>, that: Iterable<B>) => Iterable<A | B>>(arity: 2, body: <A, B>(self: Iterable<A>, that: Iterable<B>) => Iterable<A | B>): ((...args: Array<any>) => any) & (<A, B>(self: Iterable<A>, that: Iterable<B>) => Iterable<A | B>) (+1 overload)Creates a function that can be called in data-first style or data-last
(pipe-friendly) style.
When to use
Use to expose one implementation through both direct and pipe-friendly
call styles.
Details
Pass either the arity of the uncurried function or a predicate that decides
whether the current call is data-first. Arity is the common case. Use a
predicate when optional arguments make arity ambiguous.
Example (Selecting data-first or data-last style by arity)
import { Function, pipe } from "effect"
const sum = Function.dual<
(that: number) => (self: number) => number,
(self: number, that: number) => number
>(2, (self, that) => self + that)
console.log(sum(2, 3)) // 5
console.log(pipe(2, sum(3))) // 5
Example (Defining overloads with call signatures)
import { Function, pipe } from "effect"
const sum: {
(that: number): (self: number) => number
(self: number, that: number): number
} = Function.dual(2, (self: number, that: number): number => self + that)
console.log(sum(2, 3)) // 5
console.log(pipe(2, sum(3))) // 5
Example (Selecting data-first or data-last style with a predicate)
import { Function, pipe } from "effect"
const sum = Function.dual<
(that: number) => (self: number) => number,
(self: number, that: number) => number
>(
(args) => args.length === 2,
(self, that) => self + that
)
console.log(sum(2, 3)) // 5
console.log(pipe(2, sum(3))) // 5
dual(
2,
<function (type parameter) A in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>A, function (type parameter) B in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>B>(self: Iterable<A>self: interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) A in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>A>, that: Iterable<B>that: interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) B in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>B>): interface Iterable<T, TReturn = any, TNext = any>Iterable<function (type parameter) A in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>A | function (type parameter) B in <A, B>(self: Iterable<A>, that: Iterable<B>): Iterable<A | B>B> => const appendAll: <B, A>(self: Iterable<B>, that: Iterable<A>) => Iterable<A | B> (+1 overload)appendAll(that: Iterable<B>that, self: Iterable<A>self)
)Referenced by 1 symbols