The syntax is pretty simple when you understand what you need to export a feature: you need the name of the feature, the name of the concerned class, and the name of a creation procedure. What is optional is to specify an alias, an index and a calling convention. The index and calling convention are mainly used to create a DLL for windows, and the alias to export the feature under a different name.
|Export_feature||Class_name [Creation_part] ":" Feature [Optional_part]|
|Creation_part||"(" feature_name ")"|
ROOT_CLASS (make): foo @ 4 Alias my_foo call_type __stdcall
- on the class
- The class cannot be deferred or generic.
- on the feature
- It could be any feature except an attribute, an external feature or a deferred feature.
- on the creation procedure
- It must have zero argument, and no return type.
- on the alias name
- It must be a valid name for a C function.
- on the index
- It must be strictly positive.
- on the call type
- It must be a valid call type for the targeted platform (useful for Windows only). For Visual C++, the valid calling conventions are __stdcall, __cdecl and __fastcall.
For each feature the required fields are the class, the creation procedure, and of course the feature itself.
- If the feature is a creation procedure then do not specify any creation, it will use the feature as creation. For example ROOT_CLASS: make.
- If the class has no creation procedure, do not specify any creation. default_create will be automatically used.
A definition file
-- EXPORTED FEATURE(s) OF THE SHARED LIBRARY
-- SYSTEM : demo
-- CLASS [BAR]
-- Here get_string uses make_b as creation
BAR (make_b) : get_string
-- Here print_bar uses make_a as creation
BAR (make_a) : print_bar
-- CLASS [ROOT_CLASS]
-- Here the feature is also a creation
ROOT_CLASS : make
ROOT_CLASS (make) : foo
ROOT_CLASS (make) : test_bar