COM 1358 Assignment #3.
Due: Tuesday, 27 April 2000

The interpreter of Figure 3.1, extended with if and let expressions,
can be loaded into an implementation of R5RS Scheme as follows.

    % scheme
    > (load "/course/com1358/pub/r5rs.scm")
    > (load "/course/com1358/pub/define-datatype.scm")
    > (load "/course/com1358/pub/sllgen.scm")
    > (load "/course/com1358/pub/assignment3.scm")

If you are using Chez Scheme, Larceny, or DrScheme, you can substitute
"chez.scm", "larceny.scm", or "drscheme.scm" for "r5rs.scm".  If you
are using DrScheme, you may also have to substitute
"define-datatype-drscheme.scm" for "define-datatype.scm".

Do the following exercises:

    Exercise 3.1.1
    Exercise 3.2.7
    Exercise 3.3.2
    Exercise 3.4.2
    Exercise 3.4.3

Hand in a hard copy of your solution to Exercise 3.1.1 and also
a hard copy of the modified interpreter that incorporates the
changes specified in the other four exercises.  You may omit any
top-level definitions that you did not modify while doing the
exercises.