This is the actual prelude used by the Yale system.  This contains a many
small changes to the standard prelude, mostly optimizer annotations.
PreludeIO is totally different since we have flushed streams in favor
of the monad.  Primitives are defined using the Haskell to Lisp interface.

Arrays are implemented internally using destructive updates - no array
primitive involves more than one copy operation and lookup is constant
time.

The data constructors for Complex and Rational are strict.