const stream = require("stream"); const s = stream.compose( stream.Readable.from("0 1 2 3 4"), new stream.Transform({ readableObjectMode: true, transform: function (val, enc, callback) { for (const num of val.toString().split(" ")) { this.push(`${num}`); } callback(); }, }) ); s.on("readable", () => { let data; while ((data = s.read()) !== null) { console.log("read:", `${data}`); } }); s.on("end", () => { console.log("done"); });