1. A non-transitory electronic-device readable storage medium storing instructions, the instructions comprising: one or more instructions that, when executed by a processor, cause the processor to: accept a specification of an accessed class, the accessed class supporting a plurality of features that provide information or functionality on behalf of the accessed class, wherein the specification comprises: an identification of a first feature from among the plurality of features, and a list of function names to be granted access to the first feature; receive a request to access the first feature by an accessing function of an accessing class, determine whether a name of the accessing function is in the list of function names to be granted access to the first feature, and: allow the accessing function to access the first feature if the name of the accessing function is in the list of function names to be granted access to the first feature, or prevent the accessing function from accessing the first feature if the name of the accessing function is not in the list of function names to be granted access to the first feature.