ANSI-C++ Compliant RESOLVE/C++

Index:

Abstract
Calendar
Project Development
Findings and Contributions
Links and References
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Abstract:

Because of differences in the RESOLVE/C++ discipline and the ANSI-C++ standard, implementing RESOLVE/C++ foundations in ANSI-C++ and making them fully functional can be a difficult task. Things that are valid in the RESOLVE/C++ discipline may not compile with an ANSI-C++ compiler. A great deal of these reasons revolve around the difference between the RESOLVE/C++ "preserves" discipline and the readonly C++ "const" context. This projects serves to make RESOLVE/C++ more compliant with minimal loss in efficiency and maximum gain in functionality.

Calendar:

• 2:30 PM - 3:30 PM, Friday, March 2, 2001: Europa Presentation

Project Development:

At first, major changes appeared to need to be made to RESOLVE/C++ to allow it to be fully ANSI compliant. So many changes were needed that it appeared like it was impossible to make a language with all of the discipline of RESOLVE/C++ live inside true ANSI C++.

A common example of a troublesome RESOLVE/C++ statement was:


      object Character_OStream output;
      output.Open_External("");

      // This line would fail to compile because of To_Text
      output << To_Text( 5.3, 2 ) << '\n';

      output.Close_External();
      

This particular code would have to be converted to something like:


      object Character_OStream output;
      output.Open_External("");

      // Creating a modifyable temporary would fix this
      object Text temporary = To_Text( 5.3, 2 );
      output << temporary << '\n';

      output.Close_External();
      

Now, with the discovery of the mutable keyword in C++ which allows for the modifications of internal object caches and other structures even when methods are called in constant context, very minimal changes are needed to the RESOLVE/C++ language to make everything RESOLVE/C++ compliant compile with little problem in ANSI C++.

The only component which really needs this modification is the Text component. However, it would make sense to apply this to other components as well. Further research needs to be done to see exactly where mutable needs to be applied.

Findings and Contributions:

The finding of the ANSI C++ mutable not only showed that RESOLVE/C++ can be implemented very completely in ANSI C++, but it also shows that the architects of the ANSI C++ language gave a great deal of thought to software component engineering and computer science. While C++ is much more complicated than more pure OOP languages like Java, it appears to have much more potential as an academic OOP language while languages like Java and C# seem to have more practical potential.

This is surprising for me.

Links and References:

• The C++ Annotations
• Current RESOLVE/C++ Text Implementation

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