assertExists | /assert/mod.ts | std@0.222.0 | Deno

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std/assert/mod.ts>assertExists

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mod.ts (default module)

GetConstructorType

assertAlmostEquals

assertArrayIncludes

assertGreaterOrEqual

assertInstanceOf

assertLessOrEqual

assertNotEquals

assertNotInstanceOf

assertNotStrictEquals

assertObjectMatch

assertStrictEquals

assertStringIncludes

assert_almost_equals.ts

assertAlmostEquals

assert_array_includes.ts

assertArrayIncludes

assert_equals.ts

assert_exists.ts

assert_false.ts

assert_greater_or_equal.ts

assertGreaterOrEqual

assert_greater.ts

assert_instance_of.ts

GetConstructorType

assertInstanceOf

assert_is_error.ts

assert_less_or_equal.ts

assertLessOrEqual

assert_match.ts

assert_not_equals.ts

assertNotEquals

assert_not_instance_of.ts

assertNotInstanceOf

assert_not_match.ts

assert_not_strict_equals.ts

assertNotStrictEquals

assert_object_match.ts

assertObjectMatch

assert_rejects.ts

assert_strict_equals.ts

assertStrictEquals

assert_string_includes.ts

assertStringIncludes

assert_throws.ts

assertion_error.ts

unimplemented.ts

The Standard Library has been moved to JSR. See the blog post for details.

function assertExists

import { assertExists } from "https://deno.land/std@0.222.0/assert/mod.ts";

assertExists<T>(actual: T, msg?: string): asserts actual is NonNullable<T>

Make an assertion that actual is not null or undefined. If not then throw.

Examples

Example 1

import { assertExists } from "https://deno.land/std@0.222.0/assert/assert_exists.ts";

assertExists("something"); // Doesn't throw
assertExists(undefined); // Throws

Type Parameters

T

Parameters

actual: T

optional

msg: string

Returns

asserts actual is NonNullable<T>