def test_to_cps(self):
js_raw_ast = JsAst("aa")
cps_ast = _cps_js_raw(js_raw_ast, lambda x: x)
self.assertEqual(cps_ast, js_raw_ast)
atom_ast = LiteralAst(1.0)
cps_ast = to_cps(atom_ast, lambda x: x)
self.assertEqual(atom_ast, cps_ast)
let_ast = LetAst([], LiteralAst(False))
cps_ast = to_cps(let_ast, lambda x: x)
self.assertEqual(cps_ast, LiteralAst(False))
prog_ast = ProgAst([])
cps_ast = to_cps(prog_ast, lambda x: x)
self.assertEqual(cps_ast, LiteralAst(False))
prog_ast = ProgAst([LiteralAst(1)])
cps_ast = to_cps(prog_ast, lambda x: x)
self.assertEqual(cps_ast, LiteralAst(1))
prog_ast = ProgAst([LiteralAst(1), LiteralAst(2)])
cps_ast = to_cps(prog_ast, lambda x: x)
self.assertEqual(cps_ast, ProgAst([LiteralAst(1), LiteralAst(2)]))
if_ast = IfAst(LiteralAst(1), LiteralAst(2), LiteralAst(3))
cps_ast: CallAst = to_cps(if_ast, lambda x: x)
expected_ast = CallAst(
LambdaAst(
'', cps_ast.func.params,
IfAst(LiteralAst(1),
CallAst(VarAst(cps_ast.func.params[0]), [LiteralAst(2)]),
CallAst(VarAst(cps_ast.func.params[0]),
[LiteralAst(3)]))), [
LambdaAst('', cps_ast.args[0].params,
VarAst(cps_ast.args[0].params[0]))
])
self.assertEqual(cps_ast, expected_ast)
lambda_ast = LambdaAst('', ['x', 'y'], LiteralAst(1))
cps_ast = to_cps(lambda_ast, lambda x: x)
expected_ast = LambdaAst(
'', [cps_ast.params[0]] + ['x', 'y'],
CallAst(VarAst(cps_ast.params[0]), [LiteralAst(1)]))
self.assertEqual(cps_ast, expected_ast)
binary_ast = BinaryAst('+', LiteralAst(1), LiteralAst(2))
cps_ast = to_cps(binary_ast, lambda x: x)
self.assertEqual(cps_ast, binary_ast)
parse = Parser(TokenStream(InputStream("a = foo(10);")))
cps_ast = to_cps(parse(), lambda x: x)
expected_ast = CallAst(VarAst('foo'), [
LambdaAst(
'', [cps_ast.args[0].params[0]],
AssignAst(VarAst('a'), VarAst(cps_ast.args[0].params[0]))),
LiteralAst(10)
])
self.assertEqual(cps_ast, expected_ast)
def _optimize_prog_ast(self, ast: ProgAst) -> Ast:
prog = ast.prog
if not prog:
self.changes += 1
return LiteralAst(False)
if len(prog) == 1:
# self.changes += 1
return self._optimize_aux(prog[0])
if not has_side_effect(prog[0]):
self.changes += 1
return self._optimize_aux(ProgAst(prog[1:]))
return ProgAst([
self._optimize_aux(prog[0]),
self._optimize_aux(ProgAst(prog[1:]))
])
def _parse_toplevel(self) -> ProgAst:
prog = []
while not self._token_stream.eof():
prog.append(self._parse_expression())
if not self._token_stream.eof():
self._skip_punc(";")
return ProgAst(prog)
def cps_body(body: List[Ast]) -> Ast:
if not body:
return k(LiteralAst(False))
if len(body) == 1:
return to_cps(body[0], k)
return to_cps(body[0],
lambda first: ProgAst([first, cps_body(body[1:])]))
def _parse_prog(self) -> ProgAst:
"""
If the prog is empty, then it just returns FALSE.
If it has a single expression, it is returned instead of a "prog" node.
Otherwise it returns a "prog" node containing the expressions.
:return:
"""
prog = self._delimited("{", "}", ";", self._parse_expression)
# if len(prog) == 0:
# return LiteralAst(False)
# if len(prog) == 1:
# return prog[0]
return ProgAst(prog)
def test__cps_prog(self):
prog_ast = ProgAst([])
cps_ast = _cps_prog(prog_ast, lambda x: x)
self.assertEqual(cps_ast, LiteralAst(False))
prog_ast = ProgAst([LiteralAst(1)])
cps_ast = _cps_prog(prog_ast, lambda x: x)
self.assertEqual(cps_ast, LiteralAst(1))
prog_ast = ProgAst([LiteralAst(1), LiteralAst(2)])
cps_ast = _cps_prog(prog_ast, lambda x: x)
self.assertEqual(cps_ast, ProgAst([
LiteralAst(1),
LiteralAst(2),
]))
prog_ast = ProgAst([LiteralAst(1), LiteralAst(2), LiteralAst(3)])
cps_ast = _cps_prog(prog_ast, lambda x: x)
self.assertEqual(
cps_ast,
ProgAst([LiteralAst(1),
ProgAst([LiteralAst(2), LiteralAst(3)])]))
def _unwrap_iife(self, iife_ast: CallAst) -> ProgAst:
"""
unwrap iife, assign iife func params to iife args,
then execute iife func body in closure.
:param iife_ast:
:return:
"""
assert isinstance(iife_ast.func, LambdaAst)
assert isinstance(self.closure, LambdaAst)
def rename_iife_param(param: str) -> str:
"""
If iife param collides with closure, rename it.
:param param:
:return:
"""
self.closure = cast(LambdaAst, self.closure)
env: Environment = self.closure.env
var_define: VarDefine = iife_func.env.get(param)
if param in env.vars:
param = gensym(param + '$')
self.closure.iife_params.append(param)
env.define(param, True)
# change all references to iife params since we may change param names
for ref in var_define.refs:
ref.name = param
return param
iife_func = iife_ast.func
iife_args = iife_ast.args
assert len(iife_func.params) >= len(iife_args)
prog: List[Ast] = [
AssignAst(VarAst(rename_iife_param(param)), arg)
for param, arg in zip_longest(
iife_func.params, iife_args, fillvalue=LiteralAst(False))
]
prog.append(self._optimize_aux(iife_func.body))
return ProgAst(prog)
def test_evaluate(self):
ast = LiteralAst(1.0)
environment = Environment()
evaluate(ast, environment, lambda value: self.assertEqual(value, 1.0))
ast = LiteralAst(True)
environment = Environment()
evaluate(ast, environment, self.assertTrue)
ast = LiteralAst(False)
environment = Environment()
evaluate(ast, environment, self.assertFalse)
ast = LiteralAst("aaa")
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, "aaa"))
ast = BinaryAst('+', LiteralAst(1), LiteralAst(2))
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, 3.0))
ast = ProgAst([])
evaluate(ast, Environment(), self.assertFalse)
ast = ProgAst([LiteralAst(1)])
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, 1.0))
ast = ProgAst([LiteralAst(1), LiteralAst(2)])
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, 2.0))
ast = AssignAst(LiteralAst(1), LiteralAst("a"))
with self.assertRaises(Exception):
evaluate(ast, Environment(), lambda value: value)
ast = ProgAst([AssignAst(VarAst('a'), LiteralAst("foo")), VarAst('a')])
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, "foo"))
ast = AssignAst(VarAst("a"), LiteralAst("foo"))
with self.assertRaises(Exception):
evaluate(ast, Environment(Environment()), lambda value: value)
ast = CallAst(
LambdaAst("", ["a"], VarAst("a")),
[LiteralAst(1)],
)
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, 1.0))
ast = CallAst(LambdaAst("", ["a"], VarAst("a")), [LiteralAst("abc")])
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, "abc"))
# # (λ loop (n) if n > 0 then n + loop(n - 1) else 0) (10)
ast = CallAst(
LambdaAst(
"loop", ["n"],
IfAst(
BinaryAst(">", VarAst("n"), LiteralAst(0)),
BinaryAst(
"+", VarAst("n"),
CallAst(VarAst("loop"),
[BinaryAst('-', VarAst('n'), LiteralAst(1))])),
LiteralAst(0))), [LiteralAst(10)])
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, 55.0))
# # let (x) x;
ast = LetAst([VarDefAst("x", None)], VarAst("x"))
evaluate(ast, Environment(), self.assertFalse)
# # let (x = 2, y = x + 1, z = x + y) x + y + z
ast = LetAst([
VarDefAst("x", LiteralAst(2)),
VarDefAst("y", BinaryAst("+", VarAst("x"), LiteralAst(1))),
VarDefAst("z", BinaryAst("+", VarAst("x"), VarAst("y")))
], BinaryAst("+", BinaryAst("+", VarAst("x"), VarAst("y")),
VarAst("z")))
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, 10.0))
# # the second expression will result an errors,
# since x, y, z are bound to the let body
# # let (x = 2, y = x + 1, z = x + y) x + y + z; x + y + z
ast = ProgAst([
LetAst([
VarDefAst('x', LiteralAst(2)),
VarDefAst('y', BinaryAst('+', VarAst('x'), LiteralAst(1))),
VarDefAst('z', BinaryAst('+', VarAst('x'), VarAst('y')))
],
BinaryAst('+', BinaryAst('+', VarAst('x'), VarAst('y')),
VarAst('z'))),
BinaryAst('+', BinaryAst('+', VarAst('x'), VarAst('y')),
VarAst('z'))
])
with self.assertRaises(Exception):
evaluate(ast, Environment(), lambda value: value)
ast = IfAst(LiteralAst(""), LiteralAst(1), None)
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, 1.0))
ast = IfAst(LiteralAst(False), LiteralAst(1), LiteralAst(2))
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, 2.0))
ast = IfAst(LiteralAst(False), LiteralAst(1), LiteralAst(False))
evaluate(ast, Environment(), self.assertFalse)
ast = {"type": "foo", "value": 'foo'}
with self.assertRaises(Exception):
evaluate(ast, Environment(), lambda value: value)
# fib = λ(n) if n < 2 then n else fib(n - 1) + fib(n - 2);
# fib(6);
#
ast = ProgAst([
AssignAst(
VarAst('fib'),
LambdaAst(
'n', ['n'],
IfAst(
BinaryAst('<', VarAst('n'), LiteralAst(2)),
VarAst('n'),
BinaryAst(
'+',
CallAst(
VarAst('fib'),
[BinaryAst('-', VarAst('n'), LiteralAst(1))]),
CallAst(
VarAst('fib'),
[BinaryAst('-', VarAst('n'), LiteralAst(2))
]))))),
CallAst(VarAst('fib'), [LiteralAst(6)])
])
evaluate(ast, Environment(),
lambda value: self.assertEqual(value, 8.0))
ast = IfAst(LiteralAst(False), LiteralAst(1), LiteralAst(False))
evaluate(ast, Environment(), self.assertFalse)
ast = CallAst(LiteralAst(1), [])
with self.assertRaises(Exception):
evaluate(ast, Environment(), self.assertFalse)
code = """
2 + twice(3, 4)
"""
global_env = Environment()
for name, func in primitive.items():
global_env.define(name, func)
parser = Parser(TokenStream(InputStream(code)))
evaluate(parser(), global_env, lambda result: result)
def test_evaluate(self):
ast = LiteralAst(1.0)
environment = Environment()
self.assertEqual(evaluate(ast, environment), 1.0)
ast = LiteralAst(True)
environment = Environment()
self.assertEqual(evaluate(ast, environment), True)
ast = LiteralAst(False)
environment = Environment()
self.assertEqual(evaluate(ast, environment), False)
ast = LiteralAst("aaa")
self.assertEqual(evaluate(ast, Environment()), "aaa")
ast = BinaryAst('+', LiteralAst(1), LiteralAst(2))
self.assertEqual(evaluate(ast, Environment()), 3.0)
ast = ProgAst([])
self.assertEqual(evaluate(ast, Environment()), False)
ast = ProgAst([LiteralAst(1)])
self.assertEqual(evaluate(ast, Environment()), 1.0)
ast = ProgAst([LiteralAst(1), LiteralAst(2)])
self.assertEqual(evaluate(ast, Environment()), 2.0)
ast = AssignAst(LiteralAst(1), LiteralAst("a"))
with self.assertRaises(Exception):
evaluate(ast, Environment())
ast = ProgAst([AssignAst(VarAst('a'), LiteralAst("foo")), VarAst('a')])
self.assertEqual(evaluate(ast, Environment()), "foo")
ast = AssignAst(VarAst("a"), LiteralAst("foo"))
with self.assertRaises(Exception):
evaluate(ast, Environment(Environment()))
ast = CallAst(
LambdaAst("", ["a"], VarAst("a")),
[LiteralAst(1)],
)
self.assertEqual(evaluate(ast, Environment()), 1.0)
ast = CallAst(
LambdaAst("", ["a"], VarAst("a")),
[LiteralAst("abc")],
)
self.assertEqual(evaluate(ast, Environment()), "abc")
# (λ loop (n) if n > 0 then n + loop(n - 1) else 0) (10)
ast = CallAst(
LambdaAst(
"loop",
["n"],
IfAst(
BinaryAst(">", VarAst("n"), LiteralAst(0)),
BinaryAst(
"+", VarAst("n"),
CallAst(VarAst("loop"),
[BinaryAst('-', VarAst('n'), LiteralAst(1))])),
LiteralAst(0),
),
), [LiteralAst(10)])
self.assertEqual(evaluate(ast, Environment()), 55.0)
# let (x) x;
ast = LetAst([VarDefAst("x", None)], VarAst("x"))
self.assertEqual(evaluate(ast, Environment()), False)
# let (x = 2, y = x + 1, z = x + y) x + y + z
ast = LetAst([
VarDefAst("x", LiteralAst(2)),
VarDefAst("y", BinaryAst("+", VarAst("x"), LiteralAst(1))),
VarDefAst("z", BinaryAst("+", VarAst("x"), VarAst("y"))),
],
BinaryAst(
"+",
BinaryAst("+", VarAst("x"), VarAst("y")),
VarAst("z"),
))
self.assertEqual(evaluate(ast, Environment()), 10.0)
# the second expression will result an errors,
# since x, y, z are bound to the let body
# let (x = 2, y = x + 1, z = x + y) x + y + z; x + y + z
ast = ProgAst([
LetAst(
[
VarDefAst('x', LiteralAst(2)),
VarDefAst('y', BinaryAst('+', VarAst('x'), LiteralAst(1))),
VarDefAst('z', BinaryAst('+', VarAst('x'), VarAst('y'))),
],
BinaryAst(
'+',
BinaryAst('+', VarAst('x'), VarAst('y')),
VarAst('z'),
),
),
BinaryAst(
'+',
BinaryAst('+', VarAst('x'), VarAst('y')),
VarAst('z'),
),
])
with self.assertRaises(Exception):
evaluate(ast, Environment())
ast = IfAst(
LiteralAst(""),
LiteralAst(1),
None,
)
self.assertEqual(evaluate(ast, Environment()), 1.0)
ast = IfAst(
LiteralAst(False),
LiteralAst(1),
LiteralAst(2),
)
self.assertEqual(evaluate(ast, Environment()), 2.0)
ast = IfAst(
LiteralAst(False),
LiteralAst(1),
LiteralAst(False),
)
self.assertEqual(evaluate(ast, Environment()), False)
ast = {"type": "foo", "value": 'foo'}
with self.assertRaises(Exception):
evaluate(ast, Environment())