def get(cls, type_):
from pyws.functions.args.types import TypeFactory
if len(type_) < 0:
raise BadType(
'Element type (first element) is required for List type')
type_[0] = TypeFactory(type_[0])
return ListOf(*type_)
def __init__(self, name, type_, none_value=None):
"""
``name`` is the name of a field. ``type_`` is its type and
``none_value`` represents an empty value, callables are accepted as
well. ``type_`` can be specified in both standard and simplified form,
more on that read in chapter :ref:`type_specification`. ``none_value``
is used to replace ``None``, if field's ``none_value`` is ``None`` then
that of its type is used.
"""
self.name = name
self.type = TypeFactory(type_)
self.none_value = none_value
def ListOf(element_type, element_none_value=None):
"""
This function creates a list type with element type ``element_type`` and an
empty element value ``element_none_value``.
>>> from pyws.functions.args import Integer, ListOf
>>> lst = ListOf(int)
>>> issubclass(lst, List)
True
>>> lst.__name__
'IntegerList'
>>> lst.element_type == Integer
True
"""
from pyws.functions.args.types import TypeFactory
element_type = TypeFactory(element_type)
return type(element_type.__name__ + 'List', (List,), {
'element_type': element_type,
'element_none_value': element_none_value})
