switch obj := obj.(type) {
	case *types.Const:
		if w.isDeprecated(obj) {
			w.emitf("const %s //deprecated", obj.Name())
		}
		w.emitf("const %s %s", obj.Name(), w.typeString(obj.Type()))
		x := obj.Val()
		short := x.String()
		exact := x.ExactString()
		if short == exact {
			w.emitf("const %s = %s", obj.Name(), short)
		} else {
			w.emitf("const %s = %s  // %s", obj.Name(), short, exact)
		}