SOOP is a library that combines the worlds of traditional object-oriented programming and semantic ontologies. Unlike every other library out there, it does this not by mapping ontological data into the OOP-language, but by mapping the OOP-data into the ontology.
By implementing this in C++ we had many tools at our hands that allowed the creation of a great API, that is very close to normal predicate-logic without feeling foreign in C++. To demonstrate this, consider the following working code:
#include <iostream>
#include <string>
#include <soop/onto.hpp>
class person {
public:
person(std::string name): name{std::move(name)} {}
std::string name;
};
using person_e = soop::e<person>;
SOOP_MAKE_TYPECHECKED_PREDICATE(parent_of, 2, person_e, person_e)
int main() {
using namespace preds;
using namespace soop::preds;
soop::ontology o{};
o.add_type<person_e>();
o.add_predicate<parent_of_t>();
soop::variable<'p'> p;
soop::variable<'c'> c;
o.add_axiom(forall({p, c}, implies(parent_of(p, c), and_(
instance_of(p, soop::type<person_e>),
instance_of(c, soop::type<person_e>)))));
o.add_axiom(forall({p, c}, implies(parent_of(p, c), not_(parent_of(c, p)))));
person_e max{o, "Max Mustermann"};
person_e erika{o, "Erika Mustermann"};
o.add_axiom(preds::parent_of(max, erika));
soop::variable<'s'> s;
const auto& parent = std::get<0>(o.request_entities<person_e>(
exists({c}, parent_of(s, c)), s));
std::cout << parent->name << " is a parent.\n";
}This will print: “Max Mustermann is a parent.”
While some details, like the need to define semantic variables before using them in quantors, are still not perfect, we believe that this is a great step forward from existing approaches.
- A very detailed description of this project can be found in the original Bachelors thesis (German) by Florian Weber.
- We are currently preparing a paper for a workshop at the Informatik 2016-conference
For now LGPLv2 or, at your option, any later version of the LGPL.