def test_if_false(self):
st = If(Variable("x"), Assign("y", Number(1)), DoNothing())
en = {"x": Boolean(False)}
while st.reducible:
st, en = st.reduce(en)
self.assertEqual(st, DoNothing())
self.assertEqual(en["x"], Boolean(False))
def evaluate(self, environment):
"""Optimize tail recursion"""
while True:
if self.condition.evaluate(environment) == Boolean(False):
return environment
elif self.condition.evaluate(environment) == Boolean(True):
environment = self.body.evaluate(environment)
def test_if_false():
st = If(Variable("x"), Assign("y", Number(1)), DoNothing())
en = {"x": Boolean(False)}
while st.reducible:
st, en = st.reduce(en)
assert st == DoNothing()
assert en["x"] == Boolean(False)
def test_if_true(self):
st = If(Variable("x"), Assign("y", Number(1)), Assign("y", Number(2)))
self.assertEqual(str(st), "if (x) { y = 1 } else { y = 2 }")
en = {"x": Boolean(True)}
while st.reducible:
st, en = st.reduce(en)
self.assertEqual(en["y"], Number(1))
self.assertEqual(en["x"], Boolean(True))
def test_if_true():
st = If(Variable("x"), Assign("y", Number(1)), Assign("y", Number(2)))
assert str(st) == "if (x) { y = 1 } else { y = 2 }"
en = {"x": Boolean(True)}
while st.reducible:
st, en = st.reduce(en)
assert en["y"] == Number(1)
assert en["x"] == Boolean(True)
def reduce(self, environment):
if self.condition.reducible:
return (
If(
self.condition.reduce(environment),
self.consequence,
self.alternative,
),
environment,
)
else:
if self.condition == Boolean(True):
return self.consequence, environment
elif self.condition == Boolean(False):
return self.alternative, environment
def test_type(self):
n1 = Number(5)
b1 = Boolean(False)
v1 = Variable("x")
self.assertEqual(eval(n1.to_python)({}), 5)
self.assertEqual(eval(b1.to_python)({}), False)
self.assertEqual(eval(v1.to_python)({"x": 7}), 7)
def test_type(self):
self.assertEqual(Number(23).evaluate({}), Number(23))
self.assertEqual(Variable("x").evaluate({"x": Number(23)}), Number(23))
self.assertEqual(
LessThan(Add(Variable("x"), Number(2)), Variable("y")).evaluate({
"x":
Number(2),
"y":
Number(5)
}),
Boolean(True),
)
def test_type():
assert Number(23).evaluate({}) == Number(23)
assert Variable("x").evaluate({"x": Number(23)}) == Number(23)
assert LessThan(Add(Variable("x"), Number(2)), Variable("y")).evaluate({
"x":
Number(2),
"y":
Number(5)
})
n1 = Number(5)
b1 = Boolean(False)
v1 = Variable("x")
assert eval(n1.to_python)({}) == 5
assert not eval(b1.to_python)({})
assert eval(v1.to_python)({"x": 7}) == 7
def test_less():
expr = LessThan(Variable("x"), Variable("y"))
en = {"x": Number(1), "y": Number(3)}
while expr.reducible:
expr = expr.reduce(en)
assert expr == Boolean(True)
def test_boolean():
assert Boolean(True) and Boolean(True)
assert Boolean(True), Boolean(True)
assert Boolean(False), Boolean(False)
assert Boolean(True) != Boolean(False)
def evaluate(self, environment):
if self.condition.evaluate(environment) == Boolean(True):
return self.consequence.evaluate(environment)
elif self.condition.evaluate(environment) == Boolean(False):
return self.alternative.evaluate(environment)
def evaluate_with_recursion(self, environment):
if self.condition.evaluate(environment) == Boolean(True):
return self.evaluate_with_recursion(
self.body.evaluate(environment))
elif self.condition.evaluate(environment) == Boolean(False):
return environment
def test_less(self):
expr = LessThan(Variable("x"), Variable("y"))
en = {"x": Number(1), "y": Number(3)}
while expr.reducible:
expr = expr.reduce(en)
self.assertEqual(expr, Boolean(True))
def test_boolean(self):
self.assertTrue(Boolean(True) and Boolean(True))
self.assertEqual(Boolean(True), Boolean(True))
self.assertEqual(Boolean(False), Boolean(False))
self.assertNotEqual(Boolean(True), Boolean(False))