[omniORB] omni3.0.2: string sequence _var lacks constoperator[]

[Gary D. Duzan]

In Message <3A4A2B1D.E3A617AF@tumbleweed.com> ,
   randy.shoup@tumbleweed.com wrote:

=>I did a little research on my own, and it looks like this is a bug.  
=>
=>In section 6.19.1 of "Advanced CORBA Programming in C++", it claims that
=>the _var class of a sequence<T> should contain both of the following
=>methods:
=>
=>	T & operator[](CORBA:ULong);
=>	const T & operator[](CORBA::ULong) const;

   Ah, but that book is not the spec. In the IDL/C++ Mapping v2.3.1,
we have:

  1.13.4   Sequence T_var and T_out Types

  In addition to the regular operations defined for T_var and T_out
  types, the T_var and T_out for a sequence type also supports an
  overloaded operator[] that forwards requests to the operator[]
  of the underlying sequence. [footnote 12] This subscript operator
  should have the same return type as that of the corresponding
  operator on the underlying sequence type.

  [12] Note that since T_var and T_out types do not handle const
       T*, there is no need to pro-vide the const version of
       operator[] for Sequence_var and Sequence_out types.

So omniORB is correct.

					Gary Duzan
					Verizon Laboratories



=>randy.shoup@tumbleweed.com wrote:
=>> 
=>> We have been using omni2.* for a while, and now we are looking into
=>> moving to omni3.  I encountered the following problem:
=>> 
=>> We have the following in our IDL:
=>>         typedef sequence<string> StringArray;
=>> 
=>> omni2 mapped StringArray in the following way:
=>>   typedef _CORBA_Unbounded_Sequence<CORBA::String_member > StringArray;
=>>   typedef _CORBA_Sequence_Var<StringArray, CORBA::String_member >
=>> StringArray_var;
=>> 
=>> StringArray_var ended up with an operator[] const.  And we made use of
=>> the fact in our code that we could extract elements from a const
=>> StringArray_var.
=>> 
=>> However, omni3 maps these types to new classes:
=>>   class StringArray : public _CORBA_Unbounded_Sequence__String {
=>>         ...
=>>   class StringArray_var {
=>>         ...
=>> 
=>> and does not generate an operator[] const.  The only
=>> StringArray_var::operator[] is
=>>     inline _CORBA_String_element operator [] (_CORBA_ULong s) {
=>>       return (*_pd_seq)[s];
=>>     }
=>> 
=>> which is non-const.
=>> 
=>> Because it seems to use the StringArray directly, and *that* class has
=>> an operator[] const, why does the StringArray_var not have an operator[]
=>> const?
=>> 
=>> Is this a bug, or a CORBA 2.3 mapping change?
=>> 
=>> Thanks,
=>> -- Randy
=>> _________________________________________________________________
=>> Randy Shoup                                     (650)216-2038
=>> Senior Architect                                rshoup@tumbleweed.com
=>> Tumbleweed Communications Corporation
=>
=>
=>-- 
=>
=>-- Randy
=>_________________________________________________________________  
=>Randy Shoup                                     (650)216-2038  
=>Senior Architect                                rshoup@tumbleweed.com  
=>Tumbleweed Communications Corporation
=>
=>