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Re: Where to include header files - relates to last question on variable scope

Chris Hanson wrote:

On Oct 31, 2004, at 7:10 AM, Ole Voss wrote:

This also means, that I have to include the header file wherever I need it?
That could mean that the same class has to be recompiled tens of times -
right?


You need to distinguish between the declaration and the definition.

The definition needs to be compiled only once. The declaration needs to appear prior to its use in any compilation unit that needs to make use of the information in it; that's what #include and #import do.

This is true for all of C, C++, and Objective-C and is fundamental to these languages' compilation model.

So what possibilities do I have to create global variables?


You create global variables in Objective-C in exactly same way that you create them in C. Declare your global variable in a header file as extern, and define it in a single implementation file.

-- Chris


Yes, that does sound feasible but I would still have to re-include this header file in every class that I use it in?

I'm just spoilt because I've been programming Perl for over five years now and that language just does everything for you ;-)

If I include my module once - it just stays available to all my other modules and I don't have to re-include it.

C is too far away to even remember...



Thank you,


Ole.
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 >Re: Where to include header files - relates to last question on variable scope (From: Chris Hanson <email@hidden>)



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