Prolog modules are objects. This statement may surprise you. From past experience, it will also annoy some Prolog practitioners. It is not the case that the creators of Prolog module systems intended to create an object-oriented extension to Prolog. But what modules are is a function of their characteristics, not a function of their design.

Logtalk inherits but also extends and improves Prolog predicate semantics to provide clear and uniform closed world semantics, support protocols, provide consistent meta-predicate semantics, prevent misusing of multifile predicates, and prevent a number of hacks based on predicate directives that would break encapsulation. This post discusses...

Logtalk lgtunit testing tool includes a QuickCheck implementation supporting property-based testing of plain Prolog, Prolog module, and Logtalk code. The tool is portable and can be used with all Logtalk supported Prolog compilers. The QuickCheck implementation provides ...