This is the presentation which Remedy IT gave to the OMG MARS working group regarding its revised submission for the IDL to C++11 Language Mapping

1. IDL to C++11
Revised submission
OMG document mars/2012-03-32
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2. Document numbers
mars/12-03-05 (Updated IDL to C++11 Language Mapping
revised submission with errata applied - changebar)
mars/12-03-06 (Updated IDL to C++11 Language Mapping
revised submission with errata applied - clean)
mars/12-03-07 (Errata)
mars/12-03-08 (Revised submission - inventory file)
mars/12-01-02 (IDL to C++1 Language Mapping revised
submission)
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3. RFP asks for
The new mapping should be functionally equivalent to the existing
IDL to C++ mapping. While the syntax may change, an application
should be able to implement functionality identical to that which can
be achieved with the current IDL to C++ mapping.
Applications programmed using alternative language mappings
should inter operate transparently. An application utilizing this new
language mapping should have no awareness, other than
informational, of what language mapping a peer application is using.
The new language mapping should be designed to co-exist with
other technologies. Specifically, it should not interfere with the
namespaces used by other OMG specifications, or commonly used
packages.
Interoperability between the IDL to C++ and IDL to C++11 mapping
in the same compilation unit is not required.
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4. C++11
C++11 was unanimously approved August 12 th
2011
Is now formally available as ISO/IEC 14882:2011
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5. Goal of IDL to C++11
Simplified mapping for C++11
Make use of the new C++11 features to
– Gain performance
– Reduce coding errors
– Reduce amount of code
– No need to create conversion between STL/C++
types and IDL based types
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6. Enum mapping
IDL enum is mapped to the new C++11 enum
class
// IDL
enum Color { red, green, blue };
// C++
enum class Color : uint32_t { red, green, blue };
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7. C++11 type mapping
Map basic types to their C++ counterparts
IDL (w)string maps to std::(w)string
IDL sequence maps to std::vector
IDL array maps to std::array
IDL fixed maps to CORBA::Fixed
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8. Reference types
Reference types are used for
– Object reference
– Valuetypes
– Typecodes
Strong references behave as std::shared_ptr
Weak references behave as std::weak_ptr
References can only be created using
CORBA::make_reference<>
No C++ pointers can be passed to the API
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9. Client interface mapping
When defining interface Foo, than
CORBA::object_traits<Foo>::ref_type (aka
CORBA::object_reference<Foo>, aka
Foo::_ref_type) is the object reference type
C++ traits are used to determine types, no
naming rules to be remembered by the user
Narrowing using the narrow method (with
CORBA could trigger a remote call)
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10. Servant interface mapping
When defining interface Foo, than
CORBA::servant_traits<Foo>::base_type is the
base class for the user servant class
Servant references are available as
CORBA::servant_traits<Foo>::ref_type (aka
CORBA::servant_reference<Foo>)
C++ traits are used to determine types, no
naming rules to be remembered by the user
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11. Nil references
C++11 has a new type for a nil pointer: nullptr_t
References can be checked for nil by
comparing them with nullptr
Explicit bool conversion operators for usage in
for example if statements
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12. Argument passing
Argument passing for Argument passing for
basic types, and complex types:
reference types
– in: T – in: const T&
– inout: T& – inout: T&
– out: T& – out: T&
– return: T – return: T
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13. Struct/union
Struct and union now both map to a C++ class
Providing constructor(s), copy and move
operators
Set of accessors for each member:
void A (T); void A (const T&);
T A (void) const; void A (T&&);
T& A (void); const T& A (void) const;
T& A (void);
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14. Proof of concept
New language binding for TAO: IDL2C++11
Delivers new IDL compiler
Adds support libraries to use TAO with C++11
More details on http://osportal.remedy.nl and
http://www.orbzone.org
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15. Next steps
Vote 2 Vote
AB
FTF phase
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