Cons in Python

cons.py

def cons(a, b):
    return lambda fn : fn(a, b)


a_list = cons("Shane", cons("Monster", cons("Maniac", None)))


print a_list


def printy(a,b):
    if b:
        return "({} {})".format(a, b(printy))
    else:
        return "({}. nil)".format(a)
    
    
print a_list(printy)


def car(a,b):
    return a


def cdr(a,b):
    return b


print ">>", a_list(car)
print ">>", a_list(cdr)(printy)
print ">>", a_list(cdr)(cdr)(printy)