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Array

import { Array } from "@swan-io/boxed";

Array.filterMap(array, func)​

Returns an array containing the Option.Some values returned by func for each array item.

This function can be useful to refine the types of an array.

Examples
Array.filterMap([1, 2, 3], (x) =>
  isEven(x) ? Option.Some(x) : Option.None(),
); // [2]

Array.findMap(array, func)​

Returns the first Option.Some value returned by func for each array item.

Examples
Array.findMap([1, 2, 3], (x) =>
  isEven(x) ? Option.Some(x) : Option.None(),
); // Option.Some(2)

Array.find(array, predicate)​

Return the first item in the array for which predicate returns true.

The function returns an Option so that we can distinguish between a found nullish value and a not found value.

Examples
Array.find(array, (x) => x === undefined);
// Some(undefined) if found
// None if not found

Array.findIndex(array, predicate)​

Return the first index in the array for which predicate returns true.

The function returns an Option.

Examples
Array.findIndex(array, (x) => x === undefined);
// Some(index) if found
// None if not found

Array.binarySearchBy(sortedArray, item, compare)​

Performs a binary search on the array.

Returns the index of the item if there's an exact match, return the index of the first superior value if not. Return -1 if the array is empty.

Examples
const index = Array.binarySearchBy(array, "my value");

Array.zip(arrayA, arrayB)​

Create an array of pairs from two arrays.

Examples
Array.zip([1, 2, 3], ["one", "two", "three"]);
// [[1, "one"], [2, "two"], [3, "three"]]

Array.unzip(arrayOfPairs)​

Turns an array of pairs into two arrays.

Examples
Array.unzip([
  [1, "one"],
  [2, "two"],
  [3, "three"],
]);
// [[1, 2, 3], ["one", "two", "three"]]

Array.from(arrayLike)​

Array.from, reexported for convenience when Boxed Array shadows the Array constructor in scope.

Examples
Array.from({ length: 3 }, (_, key) => key); // [0, 1, 2]

Array.of(...items)​

Array.of, reexported for convenience when Boxed Array shadows the Array constructor in scope.

Examples
Array.of(1, 2, 3); // [1, 2, 3]

Array.isArray(value)​

Array.isArray, reexported for convenience when Boxed Array shadows the Array constructor in scope.

Examples
Array.isArray("");
// false

Array.isArray([1, 2, 3]);
// true