Make an assertion that actual is not null or undefined. If not then throw.
Add Package
deno add jsr:@std/assert
Import symbol
import * as mod from "@std/assert/exists";
---- OR ----
Import directly with a jsr specifier
import * as mod from "jsr:@std/assert/exists";
Add Package
npx jsr add @std/assert
Import symbol
import * as mod from "@std/assert/exists";
Add Package
yarn dlx jsr add @std/assert
Import symbol
import * as mod from "@std/assert/exists";
Add Package
pnpm dlx jsr add @std/assert
Import symbol
import * as mod from "@std/assert/exists";
Add Package
bunx jsr add @std/assert
Import symbol
import * as mod from "@std/assert/exists";