Improvements to NamedTuple's implementation, tests, and documentation
diff --git a/Lib/collections.py b/Lib/collections.py
index 6e816dc..adba81c 100644
--- a/Lib/collections.py
+++ b/Lib/collections.py
@@ -24,30 +24,29 @@
"""
field_names = s.split()
- nargs = len(field_names)
+ assert ''.join(field_names).replace('_', '').isalpha() # protect against exec attacks
+ argtxt = ', '.join(field_names)
+ reprtxt = ', '.join('%s=%%r' % name for name in field_names)
+ template = '''class %(typename)s(tuple):
+ '%(typename)s(%(argtxt)s)'
+ __slots__ = ()
+ def __new__(cls, %(argtxt)s):
+ return tuple.__new__(cls, (%(argtxt)s,))
+ def __repr__(self):
+ return '%(typename)s(%(reprtxt)s)' %% self
+ ''' % locals()
+ for i, name in enumerate(field_names):
+ template += '\t%s = property(itemgetter(%d))\n' % (name, i)
+ m = dict(itemgetter=_itemgetter)
+ exec template in m
+ result = m[typename]
+ if hasattr(_sys, '_getframe'):
+ result.__module__ = _sys._getframe(1).f_globals['__name__']
+ return result
- def __new__(cls, *args, **kwds):
- if kwds:
- try:
- args += tuple(kwds[name] for name in field_names[len(args):])
- except KeyError, name:
- raise TypeError('%s missing required argument: %s' % (typename, name))
- if len(args) != nargs:
- raise TypeError('%s takes exactly %d arguments (%d given)' % (typename, nargs, len(args)))
- return tuple.__new__(cls, args)
- repr_template = '%s(%s)' % (typename, ', '.join('%s=%%r' % name for name in field_names))
- m = dict(vars(tuple)) # pre-lookup superclass methods (for faster lookup)
- m.update(__doc__= '%s(%s)' % (typename, ', '.join(field_names)),
- __slots__ = (), # no per-instance dict (so instances are same size as tuples)
- __new__ = __new__,
- __repr__ = lambda self, _format=repr_template.__mod__: _format(self),
- __module__ = _sys._getframe(1).f_globals['__name__'],
- )
- m.update((name, property(_itemgetter(index))) for index, name in enumerate(field_names))
- return type(typename, (tuple,), m)
if __name__ == '__main__':