def test_eval_string_recursion(self):
area = eval_string('''
(define fact (lambda n (if (<= n 1) 1 (* n (fact (- n 1))))))
(fact 10)
''')
self.assertEqual(area, 3628800)
expected = 93326215443944152681699238856266700490715968264381621468592963895217599993229915608941463976156518286253697920827223758251185210916864000000000000000000000000
self.assertEqual(eval_string('(fact 100)'), expected)
def test_expr_from_tokens(self):
self.assertEqual(
expr_from_tokens(['(', '1', '2', '3', ')']),
[1, 2, 3]
)
with self.assertRaises(SyntaxError) as cm:
eval_string('(')
with self.assertRaises(SyntaxError):
expr_from_tokens([')'])
self.assertEqual(str(cm.exception), 'Unexpected ")"')
def test_eval_string_define_procedure(self):
area = eval_string('''
(define pi 3.14159)
(define area (lambda (r) (* pi (* r r))))
(area 3)
''')
self.assertEqual(area, 28.27431)
def test_eval_string(self):
data = [
('100', 100),
('100 200', 200),
('(+ 1 2 (+ 30 40 50) 3)', 126),
('(* 2 3 (* 5 6 7) 4)', 5040),
('(- 100 (- (- 50 20) 5))', 75),
('(/ 360 (/ (/ 60 2) 10))', 120),
]
for string, value in data:
self.assertEqual(eval_string(string), value)
def test_eval_string_car_cdr(self):
count = eval_string('''
(define first car)
(define rest cdr)
(define count (
lambda (item L)
(if L
(+ (equal? item (first L)) (count item (rest L)))
0
)
) )
(count 0 (list 0 1 2 3 0 0))
''')
self.assertEqual(count, 3)
count2 = eval_string('''
(count
(quote the)
(quote (the more the merrier the bigger the better))
)
''')
self.assertEqual(count2, 4)
def test_eval_string_lambda(self):
proc = eval_string('(lambda (x) (+ x 4))')
self.assertEqual(proc(10), 14)
def test_eval_string_with_vars(self):
env = Env({'a':2, 'b':30, 'c':4}, global_env)
self.assertEqual(eval_string('(+ a 3 (+ b 40 50) c)', env), 129)
