Fork

Fork the given list into two lists based on the given predicate.

🎬 Usage

<script>
    import {fork} from "@sveu/shared/lists"

    const actors = [
        {name: "Mila", age: 30},
        {name: "John", age: 40},
        {name: "Jane", age: 50},
        {name: "Emma", age: 60},
    ]

    const [young, old] = fork(actors, actor => actor.age < 50) // [{name: "Mila", age: 30}, {name: "John", age: 40}] and [{name: "Jane", age: 50}, {name: "Emma", age: 60}]
</script>

👩‍💻API

👻 Arguments

Name	Description	Type	Required
list	The list to fork	`T[]`	Yes
fn	Function to apply a condition to each item in the list	`(item: T) => boolean`	Yes

↩️ Returns

A tuple of two lists. The first list contains the items that satisfy the condition, the second list contains the items that do not satisfy the condition.

🧪 Playground

Source Code 👀

Source Code

/**
 * Fork a list into two lists based on a condition.
 *
 * @param list - List to fork
 *
 * @param fn - Function to apply a condition to each item in the list
 *
 * @returns A list of lists, where the first list contains all items that match the condition, and the second list contains all items that do not match the condition
 */
export function fork<T>(list: T[], fn: (item: T) => boolean): [T[], T[]] {
    if (!list) return [[], []]
    return list.reduce(
        (acc, item) => {
            const [a, b] = acc
            if (fn(item)) {
                return [[...a, item], b]
            } else {
                return [a, [...b, item]]
            }
        },
        [[], []] as [T[], T[]]
    )
}

Last update: 2023-02-14

Authors: Mohamed-Kaizen