[THRIFT-1786] C# Union Typing

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.9.1
• Component/s: C# - Compiler
• Patch Info: Patch Available
• Assignee: Carl Yeksigian
• Reporter: Carl Yeksigian
• Created: 11/Dec/12 20:45
• Updated: 25/May/20 00:54
• Resolved: 08/Jun/13 03:15

Description

Given the thrift IDL:

struct A {
  0: i32 value
}

union AUnion {
  0: A field1,
  1: A field2,
  2: i32 value
}

We should generate a C# subclassing tree:

class A : TBase {
  int Value { get;set; }
}

abstract class AUnion : TBase {
  abstract object Data { get; }
  protected int field;
  abstract void WriteUnionField(TProtocol tprot);

  class field1 : AUnion {
    A _data;
    override object Data { get { return _data; } }
    public field1(A data) {
      this._data = data;
      this.field = 0;
    }
  }

  class field2 : AUnion {
    A _data;
    override object Data { get { return _data; } }
    public field2(A data) {
      this._data = data;
      this.field = 1;
    }
  }

  class value : AUnion {
    int _data;
    override object Data { get { return _data; } }
    public value(int data) {
      this._data = data;
      this.field = 2;
    }
  }
}

This gives us creation syntax of:

var aunion = new AUnion.value(10);

This should be an optional parameter to the compiler since it is a breaking change to existing code.

Issue Links

• Dependency: THRIFT-4715 C# union "data" should be strongly-typed
• Dependency: THRIFT-4722 Netcore union "data" should be strongly-typed
• depends upon: THRIFT-1788 C#: Constants static constructor does not compile