cascade operator or nearest equivalent

[Daniel Davidson]

Is there any way to simulate the cascade operator (..) of Dart in 
D? This operator makes fluid initialization simple.

I am using Dart for code generation but would like to consider D 
if I can find a convenient replacement for the following 
declarative style:

     var dateRange = struct('date_range')
       ..doc = 'Basic pair of start and end dates'
       ..unitTest = true
       ..publicSection = true
       ..members = [
         member('start_date')
         ..type = 'Date',
         member('end_date')
         ..type = 'Date',
       ];

So struct is a function that returns an instance of Struct.

     class Struct extends Decls {
       ...
       /// Documentation for this D struct
       String doc;
       /// List of members of this class
       List<Member> members = [];
       bool unitTest = false;
       ...
     }

..doc = ... assigns to the Struct.doc field and returns the 
original Struct instance so that ..unitTest = true can be applied 
to the original Struct instance, etc.

What is the best way to achieve simple declarative style for very 
large initialization objects?

Thanks,
Dan