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- Item forwarded by A33 to A34
-
- Item 5805826 20-April-90 11:20PDT
-
- From: D4280 IDS, Robert Pappas,PRT
-
- To: JL.TECH Jostens Learning, Eduard Schwan,VAR
-
- cc: ALGER Alger, Jeff,VCA
- CPLUS.DEV$ C++ Interest List--Developers
- CPLUS.APPLE$ C++ Interest List--Apple Employees
- MACAPP.TECH$ MacApp Technical
-
- Sub: RE:RE: OOPascal vs. C++
-
-
- Jeff & Paul:
-
- We have embarked on a large C++/MacApp project.
-
- We chose C++ because we believe that it will be supported across more platforms
- than OPascal. Since we are a large corporation, we have to keep platforms in
- mind. And if the day that we need to switch to a different platform (heaven
- forbid), C++ will probably be the most supported language.
- The DOS world will soon have some large C++ object libraries.
-
- If I could have one more feature of C++, I would ask for nested procedures and
- the variable scoping that O Pascal has. It is not a major road-block and you
- get used to it, you don't loose any features.
-
- Our project takes 50 minutes to do a complete build. And it is only 33% done.
- We expect this value to increase to 150 minutes.
- Using a feature called load/dump with C++, the compile time is reduced by a
- factor of 2-3.
- When you ask C++ to dump something, it parses through the header files you give
- it, checking syntax and basically creating a large table of symbol mapping that
- is dumped into a file.
- So when it comes time to compile, the compiler just loads this large dump file
- quickly. If you follow Apples convention of
- #ifndef __headerfile__
- #include "headerfile.h"
- #endif
- the symbol __headerfile__ will already be defined in the dump file so the
- #include will not be executed, greatly speeding up your compile times.
-
- A very large percentage of compile times is just parsing the MacApp headers and
- your header files.
-
- Our 50 minutes becomes 20 minutes.
-
- We are also trying to get Jasiks IBS stuff to work, which doesn't help compile
- times, but helps linking times and debugging. You can do source level debugging
- like SADE, and when you find a mistake you can jump over to MPW and make your
- change, compile, and then jump back to the debugger and continue stepping
- through your source code! But, it does not work well yet.
-
- Another problem is the MacApp debugger does not display the fields of the
- object correctly. The Inspector can. So any fields method you write, you cannot
- see the values from the MacApp debugger. The problem is in the way C++ handles
- strings in a record. O Pascal can account for them, C++ can't.
-
- Also, load/dump does not work with symbols generation turned on for SADE. This
- is supposed to be fixed in the final release of C++ comming out in 2-3 weeks...
- (Right?)
-
- I also prefer C++ because I like to keep track of low level things that O
- Pascal does automatically for you. (I'm an old 68000 programmer from way back,
- counting parameters on the stack and weird stuff like that)
-
- If you use MacApp, you will never be far away from O Pascal anyway.
-
-
- Bob Pappas
- IDS Financial Services
-
-
-