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default.ok - node__assert.d.ts - Node documentation
function default.ok

Usage in Deno

```typescript import mod from "node:node__assert.d.ts"; ```
ok(
value: unknown,
message?: string | Error,
): asserts value
Tests if `value` is truthy. It is equivalent to `assert.equal(!!value, true, message)`. If `value` is not truthy, an `AssertionError` is thrown with a `message` property set equal to the value of the `message` parameter. If the `message` parameter is `undefined`, a default error message is assigned. If the `message` parameter is an instance of an `Error` then it will be thrown instead of the `AssertionError`. If no arguments are passed in at all `message` will be set to the string:`` 'No value argument passed to `assert.ok()`' ``. Be aware that in the `repl` the error message will be different to the one thrown in a file! See below for further details. ```js import assert from 'node:assert/strict'; assert.ok(true); // OK assert.ok(1); // OK assert.ok(); // AssertionError: No value argument passed to `assert.ok()` assert.ok(false, 'it\'s false'); // AssertionError: it's false // In the repl: assert.ok(typeof 123 === 'string'); // AssertionError: false == true // In a file (e.g. test.js): assert.ok(typeof 123 === 'string'); // AssertionError: The expression evaluated to a falsy value: // // assert.ok(typeof 123 === 'string') assert.ok(false); // AssertionError: The expression evaluated to a falsy value: // // assert.ok(false) assert.ok(0); // AssertionError: The expression evaluated to a falsy value: // // assert.ok(0) ``` ```js import assert from 'node:assert/strict'; // Using `assert()` works the same: assert(0); // AssertionError: The expression evaluated to a falsy value: // // assert(0) ```

Parameters

value: unknown
optional
message: string | Error

Return Type

asserts value