model.py 文件源码

def leaves(self, value):

        if value is None:
            raise ValueError('Leaves should be a list.')
        elif not isinstance(value, list) and \
                not isinstance(value, types.GeneratorType):
            raise ValueError('Leaves should be a list or a generator (%s).' % type(value))

        if self.prehashed:
            # it will create a copy of list or
            # it will create a new list based on the generator
            self._leaves = list(value)
        else:
            self._leaves = [ShardManager.hash(leaf) for leaf in value]

        if not len(self._leaves) > 0:
            raise ValueError('Leaves must contain at least one entry.')

        for leaf in self._leaves:
            if not isinstance(leaf, six.string_types):
                raise ValueError('Leaves should only contain strings.')