function isFloat64Array
          
Usage in Deno
import { isFloat64Array } from "node:util/types";
isFloat64Array(object: unknown): object is Float64Array 
      Returns true if the value is a built-in Float64Array instance.
util.types.isFloat64Array(new ArrayBuffer());  // Returns false
util.types.isFloat64Array(new Uint8Array());  // Returns false
util.types.isFloat64Array(new Float64Array());  // Returns true
object is Float64Array