def __rxor__(self, item):
"""
^ is the cons operator (equivalent to : in Haskell)
"""
unify(self.__type__(), ListType(typeof(item)))
if self.__is_evaluated:
return List(head=[item] + self.__head)
return List(head=[item] + self.__head, tail=self.__tail)
def __rxor__(self, item):
"""
^ is the cons operator (equivalent to : in Haskell)
"""
unify(self.__type__(), ListType(typeof(item)))
if self.__is_evaluated:
return List(head=[item] + self.__head)
return List(head=[item] + self.__head, tail=self.__tail)
def __add__(self, other):
"""
(+) :: [a] -> [a] -> [a]
+ is the list concatenation operator, equivalent to ++ in Haskell and +
for Python lists
"""
unify(self.__type__(), typeof(other))
if self.__is_evaluated and other.__is_evaluated:
return List(head=self.__head + other.__head)
elif self.__is_evaluated and not other.__is_evaluated:
return List(head=self.__head + other.__head, tail=other.__tail)
return List(head=self.__head, tail=itertools.chain(self.__tail, iter(other)))
def __init__(self, head=None, tail=None):
self.__head = []
self.__tail = itertools.chain([])
self.__is_evaluated = True
if head is not None and len(head) > 0:
fst = head[0]
for fst, other in zip(itertools.repeat(fst), head):
unify(typeof(fst), typeof(other))
self.__head.extend(head)
if tail is not None:
self.__tail = itertools.chain(self.__tail, tail)
self.__is_evaluated = False
return
def __init__(self, head=None, tail=None):
self.__head = []
self.__tail = itertools.chain([])
self.__is_evaluated = True
if head is not None and len(head) > 0:
fst = head[0]
for fst, other in zip(itertools.repeat(fst), head):
unify(typeof(fst), typeof(other))
self.__head.extend(head)
if tail is not None:
self.__tail = itertools.chain(self.__tail, tail)
self.__is_evaluated = False
return
def __add__(self, other):
"""
(+) :: [a] -> [a] -> [a]
+ is the list concatenation operator, equivalent to ++ in Haskell and +
for Python lists
"""
unify(self.__type__(), typeof(other))
if self.__is_evaluated and other.__is_evaluated:
return List(head=self.__head + other.__head)
elif self.__is_evaluated and not other.__is_evaluated:
return List(head=self.__head + other.__head, tail=other.__tail)
return List(head=self.__head,
tail=itertools.chain(self.__tail, iter(other)))
def __next(self):
"""
Evaluate the next element of the tail, and add it to the head.
"""
if self.__is_evaluated:
raise StopIteration
else:
try:
next_iter = next(self.__tail)
if len(self.__head) > 0:
unify(typeof(self[0]), typeof(next_iter))
self.__head.append(next_iter)
except StopIteration:
self.__is_evaluated = True
return
def __next(self):
"""
Evaluate the next element of the tail, and add it to the head.
"""
if self.__is_evaluated:
raise StopIteration
else:
try:
next_iter = next(self.__tail)
if len(self.__head) > 0:
unify(typeof(self[0]), typeof(next_iter))
self.__head.append(next_iter)
except StopIteration:
self.__is_evaluated = True
return
def __call__(self, *args, **kwargs):
# the environment contains the type of the function and the types
# of the arguments
env = {id(self):self.fn_type}
env.update({id(arg):typeof(arg) for arg in args})
ap = Var(id(self))
for arg in args:
if isinstance(arg, Undefined):
return arg
ap = App(ap, Var(id(arg)))
result_type = analyze(ap, env)
if len(self.fn_args) - 1 == len(args):
result = self.func(*args)
unify(result_type, typeof(result))
return result
return TypedFunc(functools.partial(self.func, *args, **kwargs),
self.fn_args[len(args):], result_type)
def __call__(self, *args, **kwargs):
# the environment contains the type of the function and the types
# of the arguments
env = {id(self): self.fn_type}
env.update({id(arg): typeof(arg) for arg in args})
ap = Var(id(self))
for arg in args:
if isinstance(arg, Undefined):
return arg
ap = App(ap, Var(id(arg)))
result_type = analyze(ap, env)
if len(self.fn_args) - 1 == len(args):
result = self.func(*args)
unify(result_type, typeof(result))
return result
return TypedFunc(functools.partial(self.func, *args, **kwargs),
self.fn_args[len(args):], result_type)
def __contains__(self, x):
unify(self.__type__(), ListType(typeof(x)))
for item in iter(self):
if item is x:
return True
return False
def index(self, x):
unify(self.__type__(), ListType(typeof(x)))
self.__evaluate()
return self.__head.index(x)
def count(self, x):
unify(self.__type__(), ListType(typeof(x)))
self.__evaluate()
return self.__head.count(x)
def __contains__(self, x):
unify(self.__type__(), ListType(typeof(x)))
for item in iter(self):
if item is x:
return True
return False
def index(self, x):
unify(self.__type__(), ListType(typeof(x)))
self.__evaluate()
return self.__head.index(x)
def count(self, x):
unify(self.__type__(), ListType(typeof(x)))
self.__evaluate()
return self.__head.count(x)
