function assertExistsDeprecatedDeprecated(will be removed after 1.0.0) Import from https://deno.land/std/assert/assert_exists.ts instead. import { assertExists } from "https://dotland.deno.dev/std@0.221.0/testing/asserts.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. ExamplesExample 1 import { assertExists } from "https://deno.land/std@0.221.0/testing/asserts.ts"; assertExists("something"); // Doesn't throw assertExists(undefined); // Throws Type ParametersTParametersactual: Toptionalmsg: stringReturnsasserts actual is NonNullable<T>