nochoices/dist/mod/none.js

Full featured implementation of options into typescript.

import { OptionalValue } from "./optional-value.js";
import { Option } from "./option.js";
import { Some } from "./some.js";
export class None extends OptionalValue {
    isPresent() {
        return false;
    }
    isAbsent() {
        return true;
    }
    unwrap() {
        throw new Error('unwrap over None.');
    }
    map(_fn) {
        return Option.None();
    }
    filter(_fn) {
        return Option.None();
    }
    expect(err) {
        throw err;
    }
    unwrapOr(defaultValue) {
        return defaultValue;
    }
    unwrapOrElse(defaultFn) {
        return defaultFn();
    }
    flatten() {
        return Option.None();
    }
    zip(_another) {
        return Option.None();
    }
    zipWithSome(_some) {
        return Option.None();
    }
    and(_another) {
        return Option.None();
    }
    or(_self, another) {
        return another;
    }
    xor(another) {
        return another.xorWithNone();
    }
    xorWithNone() {
        return Option.None();
    }
    xorWithSome(some) {
        return Option.Some(some.unwrap());
    }
    andThen(_fn) {
        return Option.None();
    }
    orElse(fn) {
        return fn();
    }
    getOrInsert(value) {
        return new Some(value);
    }
    getOrInsertWith(fn) {
        return new Some(fn());
    }
    takeValue() {
        return Option.None();
    }
    isSomeAnd(_andFn) {
        return false;
    }
    ifSome(_param) {
        /* no-op */
    }
    ifNone(fn) {
        fn();
    }
    toArray() {
        return [];
    }
    equalsWith(another, _equality) {
        return another.isAbsent();
    }
}