# Initialize `mparameters` from their names.
	protected fun setup_parameter_names(parameter_names: nullable Array[String]) is
		autoinit
	do
		if parameter_names == null then
			self.arity = 0
		else
			self.arity = parameter_names.length
		end

		# Create the formal parameter types
		if arity > 0 then
			assert parameter_names != null
			var mparametertypes = new Array[MParameterType]
			for i in [0..arity[ do
				var mparametertype = new MParameterType(self, i, parameter_names[i])
				mparametertypes.add(mparametertype)
			end
			self.mparameters = mparametertypes
			var mclass_type = new MGenericType(self, mparametertypes)
			self.mclass_type = mclass_type
			self.get_mtype_cache[mparametertypes] = mclass_type
		else
			self.mclass_type = new MClassType(self)
		end
	end