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c#oopc-preprocessordos-donts

Quote needed: Preprocessor usage is bad OO practice

I believe, that the usage of preprocessor directives like #if UsingNetwork is bad OO practice - other coworkers do not. I think, when using an IoC container (e.g. Spring), components can be easily configured if programmed accordingly. In this context either a propery IsUsingNetwork can be set by the IoC container or, if the "using network" implementation behaves differently, another implementation of that interface should be implemented and injected (e.g.: IService, ServiceImplementation, NetworkingServiceImplementation).

Can somebody please provide citations of OO-Gurus or references in books which basically reads "Preprocessor usage is bad OO practice if you try to configure behaviour which should be configured via an IoC container"?

I need this citations to convince coworkers to refactor...

Edit: I do know and agree that using preprocessor directives to change targetplatform specific code during compilation is fine and that is what preprocessor directives are made for. However, I think that runtime-configuration should be used rather than compiletime-configuration to get good designed and testable classes and components. In other words: Using #defines and #if's beyond what they are meant for will lead to difficult to test code and badly designed classes.

Has anybody read something along these lines and can give me so I can refer to?

Solution

  • Henry Spencer wrote a paper called #ifdef Considered Harmful.

    Also, Bjarne Stroustrup himself, in the chapter 18 of his book The Design and Evolution of C++, frowns on the use of preprocessor and wishes to eliminate it completely. However, Stroustrup also recognizes the necessity for #ifdef directive and the conditional compilation and goes on to illustrate that there is no good alternative for it in C++.

    Finally, Pete Goodliffe, in chapter 13 of his book Code Craft: The Practice of Writing Excellent Code, gives an example how, even when used for its original purpose, #ifdef can make a mess out of your code.

    Hope this helps. However, if your co-workers won't listen to reasonable arguments in the first place, I doubt book quotes will help convince them ;)