Encoder provides the method for serializing a D object into JSON format.
Constructs an Encoder object with opt.
Encodes an argument and returns the JSON.
See: http://lloyd.github.io/yajl/yajl-2.1.0/yajl__gen_8h.html#a57c29080044a7231ac0cf1fead4de4b0
See Implementation
Encoder provides the method for serializing a D object into JSON format.