Page History

...

• a boolean constant true and false ;
• a symbol S representing a boolean variable;
• (make-Not X) where X is a boolExp ;
• (make-And X Y) where X and Y are {{boolExp}} s;
• (make-Or X Y) where X and Y are {{boolExp}} s;
• (make-Implies X Y) where {{X and Y are {{boolExp}} s; or
• (make-If X Y Z) where X , Y , and Z are {{boolExp}} s.

A bool-SchemeExp is either:

• a boolean constant true or false;
• a symbol S;
• (list 'not X) where X is a bool-SchemeExp ;
• (list op X Y) where op is 'and , 'or , or 'implies where X and Y are {{bool-SchemeExp}} s;
• (list 'if X Y Z) where X , Y , and Z are {{bool-SchemeExp}} s.

The provided functions parse and unparse have the following signatures.

...