1. A library for use in programing a logic device, said library comprising: a set of general logic functions for generating an output signal x as a function of n input signals, each of said general logic functions representing a group of specific logic functions which differ from each other by inversion of an input or output signal, and each general logic function differing from another general logic function such that one general logic function can not be made the same as another general logic function only by inversion of one or more input or output signals.