Special purpose heaps are created to store different classes of data to which different rules apply. A library of functions is provided which is designed to respect the different classes of rules that apply to the different heaps, by storing data only on a heap that is designated for use with the proper class of data, and by resisting the performance of actions on data in a heap that is inconsistent with the rules that apply to the heap. The use of plural heaps in this manner discourages programmer error in which an operation is performed on data that is inconsistent with the data, since the programmer would explicitly have to copy data from one heap to the other in order to perform the action. In one example, one heap is designated for the storage of secret data, and another heap is designated for general-purpose (non-secret) data.