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Would you ever say to someone writing an application in C++:

"Think about converting some of your functions to macros"???

That is just not an option.

hmm, since when are macros bad? especially in C (not so much in C++) i could imagine situations where i would tell somebody to "convert some of your functions to macros".

I knew somebody would say that :) You're perfectly right, my example was a bit weak, however I guess you understand what I meant. You can convert just SOME of your functions to macros - I'm no C++ expert but I guess you can do that with very "small" functions. You'll do it in a few special cases to optimize very critical portions of code, you can't adopt it as a general programming practice and convert MOST of your functions to macros, and many of them you simply can't convert. Anyway, you wouldn't accept to be obliged to do that just because C++ doesn't handle function calls well.

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And converting abstractions to subpatches is much more limiting than that.

Using and reusing a great number of abstractions with many many levels of nesting is the only reasonable way (I can think of) of developing a large, complex, scalable, reusable "application" in PD.

well yes you are right. however, it is perfectly possible to do develop large complex scalable and resuable applications in Pd (sometimes i do this)

Of course it is! That's my whole point. It is possible and I do it too. Until the day comes that the application is just one bit too large and PD starts crashing or behaving weirdly.