...
Due: Friday, Feburary 26, 2010
Extra Credit
Overview
Write a Scheme function reduce
that reduces boolean expressions (represented in Scheme notation) to simplified form. For the purposes of this assignment, boolean expressions are Scheme expressions constructed from:
- the boolean constants
true
andfalse
; - boolean variables (represented by symbols other than
true
,false
,not
,and
,or
,implies
, andif
) that can be bound to eithertrue
orfalse
. - the unary operator
not
. - the binary operators
and
,or
, andimplies
, and - the ternary operator
if
.
...
The course staff is providing function parse
and unparse
in the file parser.ss that convert boolean expressions in Scheme notation to a simple inductively defined type called boolExp
and vice-versa. The coding of parse
and unparse
is not difficult, but it is tedious (like most parsing) so the course staff is providing this code rather than asking students to write it.
...