add an EncodeWriter method, using the pooled marshallers

node.go

@@ -108,6 +108,7 @@
 	return unmarshaller.Unmarshal(b, v)
 }
 
+// DecodeReader reads from the given reader and decodes a serialized IPLD cbor object into the given object.
 func DecodeReader(r io.Reader, v interface{}) error {
 	return unmarshaller.Decode(r, v)
 }
@@ -400,6 +401,11 @@
 	return marshaller.Marshal(obj)
 }
 
+// EncodeWriter marshals into the writer any object as its CBOR serialized byte representation.
+func EncodeWriter(obj interface{}, w io.Writer) error {
+	return marshaller.Encode(obj, w)
+}
+
 func toSaneMap(n map[interface{}]interface{}) (interface{}, error) {
 	if lnk, ok := n["/"]; ok && len(n) == 1 {
 		lnkb, ok := lnk.([]byte)