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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(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
functionality. For example, the display format can be changed by overriding
the :meth:`__repr__` method:
@ -496,8 +504,8 @@ the :meth:`__repr__` method:
>>> Point = namedtuple('Point', 'x y')
>>> Point.__repr__ = lambda self: 'Point(%.3f, %.3f)' % self
>>> Point(x=10, y=20)
Point(10.000, 20.000)
>>> Point(x=11, y=22)
Point(11.000, 22.000)
Default values can be implemented by starting with a prototype instance
and customizing it with :meth:`_replace`: