function isNullimport { isNull } from "https://deno.land/x/isx@1.0.0-beta.18/mod.ts"; isNull(value: unknown): value is nullWhether the value is null or not. Parametersvalue: unknown Any value. import { isNull } from "https://deno.land/x/isx@$VERSION/mod.ts" import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts" assertEquals(isNull(null), true) assertEquals(isNull(undefined), false) Returnsvalue is null