guardz/dist/typeguards/isBooleanLike.d.ts

A simple and lightweight TypeScript type guard library for runtime type validation.

import type { TypeGuardFn } from './isType';
import type { BooleanLike } from '../types/BooleanLike';
/**
 * Checks if a value can be treated as a boolean.
 *
 * This type guard validates that a value is either a boolean or can be converted to a boolean.
 * It accepts boolean values, string representations ("true", "false", "1", "0"), and numeric
 * representations (1, 0). This is useful for validating boolean values from various sources
 * like form inputs, API responses, configuration files, etc.
 *
 * @param value - The value to check
 * @param config - Optional configuration for error handling
 * @returns True if the value is a boolean or can be converted to a boolean, false otherwise
 *
 * @example
 * ```typescript
 * import { isBooleanLike } from 'guardz';
 *
 * console.log(isBooleanLike(true)); // true
 * console.log(isBooleanLike(false)); // true
 * console.log(isBooleanLike("true")); // true
 * console.log(isBooleanLike("false")); // true
 * console.log(isBooleanLike("1")); // true
 * console.log(isBooleanLike("0")); // true
 * console.log(isBooleanLike(1)); // true
 * console.log(isBooleanLike(0)); // true
 * console.log(isBooleanLike("yes")); // false
 * console.log(isBooleanLike("no")); // false
 * console.log(isBooleanLike("")); // false
 * console.log(isBooleanLike(null)); // false
 * console.log(isBooleanLike(undefined)); // false
 *
 * // With type narrowing
 * const data: unknown = getDataFromAPI();
 * if (isBooleanLike(data)) {
 *   // data is now typed as BooleanLike
 *   console.log(Boolean(data)); // Safe to convert
 * }
 * ```
 */
export declare const isBooleanLike: TypeGuardFn<BooleanLike>;