################################################################################
### Simple tests
################################################################################
# verify that instances can be pickled
from collections import namedtuple
from pickle import loads, dumps
Point = namedtuple('Point', 'x, y', True)
p = Point(x=10, y=20)
assert p == loads(dumps(p))
# test and demonstrate ability to override methods
class Point(namedtuple('Point', 'x y')):
__slots__ = ()
@property
def hypot(self):
return (self.x ** 2 + self.y ** 2) ** 0.5
def __str__(self):
return 'Point: x=%6.3f y=%6.3f hypot=%6.3f' % (self.x, self.y, self.hypot)
for p in Point(3, 4), Point(14, 5/7.):
print (p)
class Point(namedtuple('Point', 'x y')):
'Point class with optimized _make() and _replace() without error-checking'
__slots__ = ()
_make = classmethod(tuple.__new__)
def _replace(self, _map=map, **kwds):
return self._make(_map(kwds.get, ('x', 'y'), self))
print(Point(11, 22)._replace(x=100))
Point3D = namedtuple('Point3D', Point._fields + ('z',))
print(Point3D.__doc__)
import doctest, collections
TestResults = namedtuple('TestResults', 'failed attempted')
print(TestResults(*doctest.testmod(collections)))
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