assertIsError | /assert/assert_is_error.ts | std@0.223.0

function assertIsError

import { assertIsError } from "https://dotland.deno.dev/std@0.223.0/assert/assert_is_error.ts";

assertIsError<E extends Error = Error>(

error: unknown,

ErrorClass?: new (...args: any[]) => E,

msgMatches?: string | RegExp,

msg?: string,

): asserts error is E

Make an assertion that error is an Error. If not then an error will be thrown. An error class and a string that should be included in the error message can also be asserted.

Examples

Example 1

import { assertIsError } from "https://deno.land/std@0.223.0/assert/assert_is_error.ts";

assertIsError(null); // Throws
assertIsError(new RangeError("Out of range")); // Doesn't throw
assertIsError(new RangeError("Out of range"), SyntaxError); // Throws
assertIsError(new RangeError("Out of range"), SyntaxError, "Out of range"); // Doesn't throw
assertIsError(new RangeError("Out of range"), SyntaxError, "Within range"); // Throws

Type Parameters

optional

E extends Error = Error

Parameters

error: unknown

optional

ErrorClass: new (...args: any[]) => E

optional

msgMatches: string | RegExp

optional

msg: string

Returns

asserts error is E