Definition file

      1. Syntax
      2. Example
      3. Constraints
      4. A definition file

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 ")"
Optional_part [Index_part] [Alias_part]
Index_part "@" integer
Alias_part "Alias" alias_name
Call_type_part "call_type" call_type_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