typedash/dist/assert/index.d.cts

modern, type-safe collection of utility functions

/**
 * Asserts that a condition is true, throwing an Error if it is not.
 * @param condition A condition that should be true
 * @param message A message to use in the Error that will be thrown if the condition is falsy
 * @throws An `AssertionError` if the condition is falsy
 * @example
 * ```ts
 * function doWork(value: number | undefined) {
 *   assert(value !== undefined, 'value should be defined');
 *   // value is now narrowed to number
 *
 *   return value + 1;
 * }
 * ```
 * @example
 * ```ts
 * assert(1 === 1); // OK
 * assert(1 === 2); // throws AssertionError
 * assert(1 === 2, '1 should equal 2'); // throws AssertionError: 1 should equal 2
 * ```
 */
declare function assert(condition?: unknown, message?: string): asserts condition;
/**
 * An error that is thrown when an assertion is not satisfied.
 * Thrown by {@link assert}.
 */
declare class AssertionError extends Error {
    constructor(message?: string);
}

export { AssertionError, assert };