private FieldReference ResolveStateClassField(TypeReference role)
{
var stateTypeDefinition = role.ResolveStateClass();
var stateTypeReference = new MemberResolver(role).ResolveMatchingType(stateTypeDefinition);
var fieldDefinition = _targetType.Fields.
SingleOrDefault(fd => TypeMatcher.IsMatch(fd.FieldType, stateTypeReference));
if (fieldDefinition == null) return null; // TODO: this is because the role was already implemented in a base class; it should be checked before, possibly in the conflict resolution stage
return new FieldReference(
fieldDefinition.Name,
fieldDefinition.FieldType) {
DeclaringType = fieldDefinition.DeclaringType.ResolveGenericArguments()
};
}