Matching in binding maps should be done on structures if possible

[Leo-Nogismus]

In binding_map.cpp, when calling intersect() or contains() on StructureValue s and AtomValues, we only do exact matching of atoms, or, in the case of floats, the match is calculated with Utils::Equal(). This should be changed to allow the matching of objects, especially for StructureValues. This would allow for user-defined equals-operators, allowing for more complex matching. For example, we could define angle as its own class and use user-defined equals-operators to check for 2*pi angle difference. Or use more complex structures for direct matching.

The code would need to be changed to utilize user-defined operators in the following three code segments.

AERA/r_exec/binding_map.cpp

Lines 204 to 213 in f774c52

	bool AtomValue::contains(const Atom a) const {
	if (atom_ == a)
	return true;
	if (atom_.isFloat() && a.isFloat())
	return Utils::Equal(atom_.asFloat(), a.asFloat());
	return false;
	}

AERA/r_exec/binding_map.cpp

Lines 293 to 313 in f774c52

	bool StructureValue::contains(const Atom *s) const {
	if (structure_->code(0) != s[0])
	return false;
	if (structure_->code(0).getDescriptor() == Atom::TIMESTAMP)
	return Utils::Synchronous(Utils::GetTimestamp(&structure_->code(0)), Utils::GetTimestamp(s));
	for (uint16 i = 1; i < structure_->code_size(); ++i) {
	Atom a = structure_->code(i);
	Atom _a = s[i];
	if (a == _a)
	continue;
	if (a.isFloat() && _a.isFloat())
	return Utils::Equal(a.asFloat(), _a.asFloat());
	return false;
	}
	return true;
	}

AERA/r_exec/binding_map.cpp

Lines 720 to 729 in f774c52

	bool BindingMap::match_atom(Atom o_atom, Atom p_atom) {
	if (p_atom == o_atom)
	return true;
	if (p_atom.isFloat() && o_atom.isFloat())
	return Utils::Equal(o_atom.asFloat(), p_atom.asFloat());
	return false;
	}