implementation of rational numbers

[Daniel L. Weinreb <dlw at MIT-AI>]

Since your suggestion only affects the internal implementation of
rationals and is not visible at the language definition level, it should
be easy to play with once rationals are implemented.  It should be noted
that (presumably) it is defined that the printed representation of a
rational always appears as if the rational were in lowest terms; writing
the printer in the obvious way (using NUMERATOR and DENOMINATOR) would
correctly produce this behavior anyway.