(documentationFrontFnEnglishLanguage "A Function that maps an Object to the side that generally receives the most attention or that typically faces the direction in which the Object moves. Note that this is a partial function, since some Objects do not have sides, e.g. apples and spheres. Note too that the range of this Function is indefinite in much the way that ImmediateFutureFn and ImmediatePastFn are indefinite. Although this indefiniteness is undesirable from a theoretical standpoint, it does not have significant practical implications, since there is widespread intersubjective agreement about the most common cases.")