TypeScript/src/lib/es2023.array.d.ts

interface Array<T> {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends T>(predicate: (value: T, index: number, array: T[]) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: T, index: number, array: T[]) => unknown, thisArg?: any): T | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: T, index: number, array: T[]) => unknown, thisArg?: any): number;
}

interface ReadonlyArray<T> {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends T>(predicate: (value: T, index: number, array: readonly T[]) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: T, index: number, array: readonly T[]) => unknown, thisArg?: any): T | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: T, index: number, array: readonly T[]) => unknown, thisArg?: any): number;
}

interface Int8Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends number>(predicate: (value: number, index: number, array: Int8Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: number, index: number, array: Int8Array) => unknown, thisArg?: any): number | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: number, index: number, array: Int8Array) => unknown, thisArg?: any): number;
}

interface Uint8Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends number>(predicate: (value: number, index: number, array: Uint8Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: number, index: number, array: Uint8Array) => unknown, thisArg?: any): number | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: number, index: number, array: Uint8Array) => unknown, thisArg?: any): number;
}

interface Uint8ClampedArray {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends number>(predicate: (value: number, index: number, array: Uint8ClampedArray) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: number, index: number, array: Uint8ClampedArray) => unknown, thisArg?: any): number | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: number, index: number, array: Uint8ClampedArray) => unknown, thisArg?: any): number;
}

interface Int16Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends number>(predicate: (value: number, index: number, array: Int16Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: number, index: number, array: Int16Array) => unknown, thisArg?: any): number | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: number, index: number, array: Int16Array) => unknown, thisArg?: any): number;
}

interface Uint16Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends number>(predicate: (value: number, index: number, array: Uint16Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: number, index: number, array: Uint16Array) => unknown, thisArg?: any): number | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: number, index: number, array: Uint16Array) => unknown, thisArg?: any): number;
}

interface Int32Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends number>(predicate: (value: number, index: number, array: Int32Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: number, index: number, array: Int32Array) => unknown, thisArg?: any): number | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: number, index: number, array: Int32Array) => unknown, thisArg?: any): number;
}

interface Uint32Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends number>(predicate: (value: number, index: number, array: Uint32Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: number, index: number, array: Uint32Array) => unknown, thisArg?: any): number | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: number, index: number, array: Uint32Array) => unknown, thisArg?: any): number;
}

interface Float32Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends number>(predicate: (value: number, index: number, array: Float32Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: number, index: number, array: Float32Array) => unknown, thisArg?: any): number | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: number, index: number, array: Float32Array) => unknown, thisArg?: any): number;
}

interface Float64Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends number>(predicate: (value: number, index: number, array: Float64Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: number, index: number, array: Float64Array) => unknown, thisArg?: any): number | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: number, index: number, array: Float64Array) => unknown, thisArg?: any): number;
}

interface BigInt64Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends bigint>(predicate: (value: bigint, index: number, array: BigInt64Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: bigint, index: number, array: BigInt64Array) => unknown, thisArg?: any): bigint | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: bigint, index: number, array: BigInt64Array) => unknown, thisArg?: any): number;
}

interface BigUint64Array {
    /**
     * Returns the value of the last element in the array where predicate is true, and undefined
     * otherwise.
     * @param predicate findLast calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found, findLast
     * immediately returns that element value. Otherwise, findLast returns undefined.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLast<S extends bigint>(predicate: (value: bigint, index: number, array: BigUint64Array) => value is S, thisArg?: any): S | undefined;
    findLast(predicate: (value: bigint, index: number, array: BigUint64Array) => unknown, thisArg?: any): bigint | undefined;

    /**
     * Returns the index of the last element in the array where predicate is true, and -1
     * otherwise.
     * @param predicate findLastIndex calls predicate once for each element of the array, in descending
     * order, until it finds one where predicate returns true. If such an element is found,
     * findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
     * @param thisArg If provided, it will be used as the this value for each invocation of
     * predicate. If it is not provided, undefined is used instead.
     */
    findLastIndex(predicate: (value: bigint, index: number, array: BigUint64Array) => unknown, thisArg?: any): number;
}