olasd
commented
11 years ago Would something along the lines of
from hy.models import HyObject
from hy.models.list import HyList
class HyCons(HyObject):
"""
HyCons: a cons object.
Building a HyCons of something and a HyList builds a HyList
"""
__slots__ = ["car", "cdr"]
def __new__(cls, car=None, cdr=None):
if isinstance(cdr, HyList):
return cdr.__class__([car] + cdr)
else:
return super(HyCons, cls).__new__(cls)
def __init__(self, car=None, cdr=None):
self.car = car
self.cdr = cdr
def __repr__(self):
return "(%s . %s)" % (repr(self.car), repr(self.cdr))work?
jd
ghost
algernon
paultag
theanalyst
We need cons support to be called a Lisp.
Here's an idea of implementation.
hy.model.cons.HyConsclass that is a list of only 2 elements@builds(cons)intocompiler.pythat create a function taking 2 arguments and returning aHyConsof these 2 arguments.@builds(cons)so if you try to(cons a b)where b is anHyConsinstance, you'll return anHyList([a b]). So a(cons 1 (cons 2 (cons 3 4)))buildsHyList([1 2 HyCons(3, 4)]).Alternatively, 3. may be not a special case of
@builds(cons)but could be implemented on top ofHyConsusing__iter__,__getitem__, etc functions to emulate a list behaviour. Though that may be less optimal.