return x
else:
return f(Thunk([f, x, tail(copy(xs))]).bind(apply(fold)),
head(copy(xs)))
@curry
def map(f, xs):
return xs.map(lambda xs: map(f, xs))
@curry
def filter(f, xs):
return xs.map(lambda xs: filter(f, xs))
def do(exp, **kwargs):
load = Thunk({})
def loadKeypair(k, v):
return v.map(lambda v: {k: v})
def apply(load, k, v):
load.bind(lambda ls: loadKeypair(k, v).map(lambda p: dict(ls, **p)))
for k, v in kwargs.iteritems():
apply(load, k, v)
return load.bind(lambda ls: exp(**ls))
@curry
def add(a, b):
return do(lambda a, b: Thunk(a + b), a=a, b=b)
assert unroll(lambda me, a, b: add(a, b))(Thunk(1), Thunk(2)) == 3
assert unroll(lambda me: fold(add, Thunk(0), Thunk([1,2,3])))() == 6
def match(x, p):
return p(unroll(lambda me: x)())
def assertThunksEqual(self, a, b):
thunk1 = unroll(lambda me: a)()
thunk2 = unroll(lambda me: b)()
self.assertEqual(thunk1, thunk2)