function Deno.readDirSync
          
readDirSync(path: string | URL): Iterable<DirEntry> 
      Synchronously reads the directory given by path and returns an iterable
of Deno.DirEntry. The order of entries is not guaranteed.
for (const dirEntry of Deno.readDirSync("/")) {
  console.log(dirEntry.name);
}
Throws error if path is not a directory.
Requires allow-read permission.
Iterable<DirEntry>