simplified axiom

include/loki/details/pddl/axiom.hpp

@@ -28,12 +28,11 @@ class AxiomImpl
 {
 private:
     size_t m_index;
-    ParameterList m_parameters;
-    Predicate m_derived_predicate;  ///< the predicate from the introduced :derived-predicates section
-    Literal m_subtyped_literal;     ///< the axiom may use subtypes
+    ParameterList m_parameters;  // the updated parameters which might contain subtypes.
+    Literal m_literal;
     Condition m_condition;
 
-    AxiomImpl(size_t index, ParameterList parameters, Predicate derived_predicate, Literal subtyped_literal, Condition condition);
+    AxiomImpl(size_t index, ParameterList parameters, Literal subtyped_literal, Condition condition);
 
     // Give access to the constructor.
     template<typename T, typename Hash, typename EqualTo>
@@ -48,17 +47,10 @@ class AxiomImpl
 
     size_t get_index() const;
     const ParameterList& get_parameters() const;
-    const Predicate& get_derived_predicate() const;
-    const Literal& get_subtyped_literal() const;
+    const Literal& get_literal() const;
     const Condition& get_condition() const;
 
-    auto identifying_members() const
-    {
-        return std::forward_as_tuple(std::as_const(m_parameters),
-                                     std::as_const(m_derived_predicate),
-                                     std::as_const(m_subtyped_literal),
-                                     std::as_const(m_condition));
-    }
+    auto identifying_members() const { return std::forward_as_tuple(std::as_const(m_parameters), std::as_const(m_literal), std::as_const(m_condition)); }
 };
 
 extern std::ostream& operator<<(std::ostream& out, const AxiomImpl& element);

include/loki/details/pddl/repositories.hpp

@@ -260,7 +260,7 @@ class PDDLRepositories
     Action
     get_or_create_action(std::string name, size_t original_arity, ParameterList parameters, std::optional<Condition> condition, std::optional<Effect> effect);
 
-    Axiom get_or_create_axiom(ParameterList parameters, Predicate derived_predicate, Literal subtyped_literal, Condition condition);
+    Axiom get_or_create_axiom(ParameterList parameters, Literal subtyped_literal, Condition condition);
 
     OptimizationMetric get_or_create_optimization_metric(OptimizationMetricEnum metric, FunctionExpression function_expression);
 

src/pddl/axiom.cpp

@@ -26,11 +26,10 @@
 
 namespace loki
 {
-AxiomImpl::AxiomImpl(size_t index, ParameterList parameters, Predicate derived_predicate, Literal subtyped_literal, Condition condition) :
+AxiomImpl::AxiomImpl(size_t index, ParameterList parameters, Literal literal, Condition condition) :
     m_index(index),
     m_parameters(std::move(parameters)),
-    m_derived_predicate(std::move(derived_predicate)),
-    m_subtyped_literal(std::move(subtyped_literal)),
+    m_literal(std::move(literal)),
     m_condition(std::move(condition))
 {
 }
@@ -39,9 +38,7 @@ size_t AxiomImpl::get_index() const { return m_index; }
 
 const ParameterList& AxiomImpl::get_parameters() const { return m_parameters; }
 
-const Predicate& AxiomImpl::get_derived_predicate() const { return m_derived_predicate; }
-
-const Literal& AxiomImpl::get_subtyped_literal() const { return m_subtyped_literal; }
+const Literal& AxiomImpl::get_literal() const { return m_literal; }
 
 const Condition& AxiomImpl::get_condition() const { return m_condition; }
 

src/pddl/formatter.cpp

@@ -72,8 +72,8 @@ void PDDLFormatter::write(const AtomImpl& element, std::ostream& out)
 
 void PDDLFormatter::write(const AxiomImpl& element, std::ostream& out)
 {
-    out << std::string(m_indent, ' ') << "(:derived " << element.get_derived_predicate()->get_name();
-    for (size_t i = 0; i < element.get_subtyped_literal()->get_atom()->get_terms().size(); ++i)
+    out << std::string(m_indent, ' ') << "(:derived " << element.get_literal()->get_atom()->get_predicate()->get_name();
+    for (size_t i = 0; i < element.get_literal()->get_atom()->get_terms().size(); ++i)
     {
         out << " ";
         write(*element.get_parameters()[i], out);

src/pddl/parser/structure.cpp

@@ -131,7 +131,7 @@ Axiom parse(const ast::Axiom& node, Context& context)
         parameters.push_back(context.factories.get_or_create_parameter(variable, base_types));
     }
 
-    const auto axiom = context.factories.get_or_create_axiom(parameters, predicate, literal, condition);
+    const auto axiom = context.factories.get_or_create_axiom(parameters, literal, condition);
     context.positions.push_back(axiom, node);
     return axiom;
 }

src/pddl/repositories.cpp

@@ -372,10 +372,9 @@ Action PDDLRepositories::get_or_create_action(std::string name,
         .get_or_create(std::move(name), std::move(original_arity), std::move(parameters), std::move(condition), std::move(effect));
 }
 
-Axiom PDDLRepositories::get_or_create_axiom(ParameterList parameters, Predicate derived_predicate, Literal subtyped_literal, Condition condition)
+Axiom PDDLRepositories::get_or_create_axiom(ParameterList parameters, Literal subtyped_literal, Condition condition)
 {
-    return boost::hana::at_key(m_repositories, boost::hana::type<AxiomImpl> {})
-        .get_or_create(std::move(parameters), derived_predicate, subtyped_literal, condition);
+    return boost::hana::at_key(m_repositories, boost::hana::type<AxiomImpl> {}).get_or_create(std::move(parameters), subtyped_literal, condition);
 }
 
 OptimizationMetric PDDLRepositories::get_or_create_optimization_metric(OptimizationMetricEnum metric, FunctionExpression function_expression)