-(define (cond-predicate clause) (car clause))
-(define (cond-actions clause) (cdr clause))
-(define (cond-else-clause? clause)
- (eq? (cond-predicate clause) 'else))
-
-(define (expand-clauses clauses)
- (display "Expanding cond clauses...")
- (if (null? clauses)
- (none)
- (let ((first (car clauses))
- (rest (cdr clauses)))
- (if (cond-else-clause? first)
- (if (null? rest)
- `(begin ,@(cond-actions first))
- (error "else clause isn't last in cond expression."))
- `(if ,(cond-predicate first)
- (begin ,@(cond-actions first))
- ,(expand-clauses rest))))))
-
-(define-macro (cond . clauses)
- (if (null? clauses)
- (error "cond requires at least one clause.")
- (expand-clauses clauses)))
+((lambda ()
+ (define (cond-predicate clause) (car clause))
+ (define (cond-actions clause) (cdr clause))
+ (define (cond-else-clause? clause)
+ (eq? (cond-predicate clause) 'else))
+
+ (define (expand-clauses clauses)
+ (if (null? clauses)
+ (none)
+ (let ((first (car clauses))
+ (rest (cdr clauses)))
+ (if (cond-else-clause? first)
+ (if (null? rest)
+ `(begin ,@(cond-actions first))
+ (error "else clause isn't last in cond expression."))
+ `(if ,(cond-predicate first)
+ (begin ,@(cond-actions first))
+ ,(expand-clauses rest))))))
+
+ (define-macro (cond . clauses)
+ (if (null? clauses)
+ (error "cond requires at least one clause.")
+ (expand-clauses clauses)))
+ ))