When used within an object, this directive defines a goal to be called after the object has been loaded into memory. When used at a global level within a source file, this directive defines a goal to be called after the compiled source file is loaded into memory.

Multiple initialization directives can be used in a source file or in an object. Their goals will be called in order at loading time.


Categories and protocols cannot contain initialization/1 directives as the initialization goals would lack a complete execution context that is only available for objects.

Although technically a global initialization/1 directive in a source file is a Prolog directive, calls to Logtalk built-in predicates from it are usually compiled to improve performance and providing better support for embedded applications.


Some backend Prolog compilers declare initialization as an operator for a lighter syntax. But this makes the code non-portable and is a practice best avoided.

Template and modes



% call the init/0 predicate after loading the
% source file containing the directive:
:- initialization(init).