Exercise 4.14: Eva Lu Ator and Louis Reasoner
are each experimenting with the metacircular evaluator.  Eva types in the
definition of map, and runs some test programs that use it.  They work
fine.  Louis, in contrast, has installed the system version of map as a
primitive for the metacircular evaluator.  When he tries it, things go terribly
wrong.  Explain why Louis’s map fails even though Eva’s works.