typescript-functional-extensions/dist/esm/maybe.utilities.js

A TypeScript implementation of synchronous and asynchronous Maybe and Result monads

import { Maybe } from './maybe.js';
import { isDefined } from './utilities.js';
/**
 * Converts string, null, or undefined values into a Maybe<string>. Throws an error for defined, non-string values.
 * @param value
 * @returns Maybe.some when value is defined and non-empty, Maybe.none otherwise.
 */
export function emptyStringAsNone(value) {
    if (!isDefined(value)) {
        return Maybe.none();
    }
    if (typeof value !== 'string') {
        throw Error('Value must be a string');
    }
    if (value === '') {
        return Maybe.none();
    }
    return Maybe.some(value);
}
const whiteSpaceRegex = /^\s*$/g;
/**
 * Converts string, null, or undefined values into a Maybe<string>. Throws an error for defined, non-string values.
 * @param value
 * @returns Maybe.some when value is defined, non-empty, and non-whitespace, Maybe.none otherwise.
 */
export function emptyOrWhiteSpaceStringAsNone(value) {
    if (!isDefined(value)) {
        return Maybe.none();
    }
    if (typeof value !== 'string') {
        throw Error('Value must be a string');
    }
    if (whiteSpaceRegex.test(value)) {
        return Maybe.none();
    }
    return Maybe.some(value);
}
/**
 * Converts number, null, or undefined values into a Maybe<number>. Throws an error for defined, non-number values.
 * @param value
 * @returns Maybe.some when value is defined and non-zero, Maybe.none otherwise.
 */
export function zeroAsNone(value) {
    if (!isDefined(value)) {
        return Maybe.none();
    }
    if (typeof value !== 'number') {
        throw Error('Value must be a number');
    }
    if (value === 0) {
        return Maybe.none();
    }
    return Maybe.some(value);
}