Framework Headers And NT Compile Time

When building custom frameworks, many OPENSTEP and WebObjects developers working on the OPENSTEP for Mach platform use framework headers, combined with pre-compiled headers, to speed up the development cycle. A framework header is a header that include definitions for all classes in a framework. Together, these two elements can result in quicker compiles and eliminate the need to use separate #import or #include statements for each class your project uses.

Under Windows NT, pre-compiled headers are not an option. However, using unstripped framework headers for custom frameworks causes an increase in DLL size for each #import statement. This can increase compile time, slow down the debugger, and slow your development cycle substantially. Each header file which imports a framework will increase the size of the DLL. Therefore, unless you are using a framework with stripped headers, such as Apple's Foundation and WebObjects frameworks, always use a separate #import or @class statement to include only those files needed by a specific header. For example, instead of

#import <MyFramework/MyFramework.h> //import every header in the framework
use the faster:

#import <MyFramework/SomeClass.h> //a class need by this object
#import <MyFramework/OtherClass.h> //another class needed by this object