"""
An object subclass for Python 2 that gives new-style classes written in the
style of Python 3 (with ``__next__`` and unicode-returning ``__str__`` methods)
the appropriate Python 2-style ``next`` and ``__unicode__`` methods for compatible.
Example use::
from builtins import object
my_unicode_str = u'Unicode string: \u5b54\u5b50'
class A(object):
def __str__(self):
return my_unicode_str
a = A()
print(str(a))
# On Python 2, these relations hold:
assert unicode(a) == my_unicode_string
assert str(a) == my_unicode_string.encode('utf-8')
Another example::
from builtins import object
class Upper(object):
def __init__(self, iterable):
self._iter = iter(iterable)
def __next__(self): # note the Py3 interface
return next(self._iter).upper()
def __iter__(self):
return self
assert list(Upper('hello')) == list('HELLO')
"""
class newobject(object):
"""
A magical object class that provides Python 2 compatibility methods::
next
__unicode__
__nonzero__
Subclasses of this class can merely define the Python 3 methods (__next__,
__str__, and __bool__).
"""
def next(self):
if hasattr(self, '__next__'):
return type(self).__next__(self)
raise TypeError('newobject is not an iterator')
def __unicode__(self):
# All subclasses of the builtin object should have __str__ defined.
# Note that old-style classes do not have __str__ defined.
if hasattr(self, '__str__'):
s = type(self).__str__(self)
else:
s = str(self)
if isinstance(s, unicode):
return s
else:
return s.decode('utf-8')
def __nonzero__(self):
if hasattr(self, '__bool__'):
return type(self).__bool__(self)
if hasattr(self, '__len__'):
return type(self).__len__(self)
# object has no __nonzero__ method
return True
# Are these ever needed?
# def __div__(self):
# return self.__truediv__()
# def __idiv__(self, other):
# return self.__itruediv__(other)
def __long__(self):
if not hasattr(self, '__int__'):
return NotImplemented
return self.__int__() # not type(self).__int__(self)
# def __new__(cls, *args, **kwargs):
# """
# dict() -> new empty dictionary
# dict(mapping) -> new dictionary initialized from a mapping object's
# (key, value) pairs
# dict(iterable) -> new dictionary initialized as if via:
# d = {}
# for k, v in iterable:
# d[k] = v
# dict(**kwargs) -> new dictionary initialized with the name=value pairs
# in the keyword argument list. For example: dict(one=1, two=2)
# """
# if len(args) == 0:
# return super(newdict, cls).__new__(cls)
# elif type(args[0]) == newdict:
# return args[0]
# else:
# value = args[0]
# return super(newdict, cls).__new__(cls, value)
def __native__(self):
"""
Hook for the future.utils.native() function
"""
return object(self)
__slots__ = []
__all__ = ['newobject']
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