import { isTransformStream } from "https://deno.land/x/deno@v1.0.0/cli/js/web/streams/internals.ts";
Returns
x is TransformStreamImpl<any, any>
x/deno/cli/js/web/streams/internals.ts>isTransformStream
import { isTransformStream } from "https://deno.land/x/deno@v1.0.0/cli/js/web/streams/internals.ts";