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This commit is contained in:
Raymond Hettinger 2007-12-14 21:51:50 +00:00
parent 07ae83f840
commit e846f38c77
1 changed files with 10 additions and 2 deletions
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Doc/library/collections.rst
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@ -488,6 +488,14 @@ two additonal methods and a read-only attribute.
>>> Pixel(11, 22, 128, 255, 0) >>> Pixel(11, 22, 128, 255, 0)
Pixel(x=11, y=22, red=128, green=255, blue=0)' Pixel(x=11, y=22, red=128, green=255, blue=0)'
To retrieve a field whose name is stored in a string, use the :func:`getattr`
function:
::
>>> getattr(p, 'x')
11
Since a named tuple is a regular Python class, it is easy to add or change Since a named tuple is a regular Python class, it is easy to add or change
functionality. For example, the display format can be changed by overriding functionality. For example, the display format can be changed by overriding
the :meth:`__repr__` method: the :meth:`__repr__` method:
@ -496,8 +504,8 @@ the :meth:`__repr__` method:
>>> Point = namedtuple('Point', 'x y') >>> Point = namedtuple('Point', 'x y')
>>> Point.__repr__ = lambda self: 'Point(%.3f, %.3f)' % self >>> Point.__repr__ = lambda self: 'Point(%.3f, %.3f)' % self
>>> Point(x=10, y=20) >>> Point(x=11, y=22)
Point(10.000, 20.000) Point(11.000, 22.000)
Default values can be implemented by starting with a prototype instance Default values can be implemented by starting with a prototype instance
and customizing it with :meth:`_replace`: and customizing it with :meth:`_replace`: