name | predicate? | procedure |
---|---|---|
symbol | expression | expression |
symbol | expression | expression |
nary1 | (lambda (a) (not (null? a))) | identity |
nary | (lambda (a) #t) | identity |
boolean | (lambda (a) (or (null? a) (and (pair? a) (null? (cdr a)) (boolean? (car a))))) |
(lambda (a) (if (null? a) #f (car a))) |
optional | (lambda (lambda (a) (or (null? a) (and (pair? a) (null? (cdr a)))))) |
identity |
single | (lambda (a) (and (pair? a) (null? (cdr a)))) | car |