mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-12-09 02:35:14 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 10

Simplify and speedup _asdict() for named tuples.

Browse source
This commit is contained in:
Raymond Hettinger 2007-12-18 22:21:27 +00:00
parent 0423698bc3
commit 8777bcae27
2 changed files with 7 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

4
Doc/library/collections.rst
View file

@ -394,9 +394,9 @@ Example::
def __repr__(self): def __repr__(self):
return 'Point(x=%r, y=%r)' % self return 'Point(x=%r, y=%r)' % self
def _asdict(self): def _asdict(t):
'Return a new dict which maps field names to their values' 'Return a new dict which maps field names to their values'
return dict(zip(('x', 'y'), self)) return {'x': t[0], 'y': t[1]}
def _replace(self, **kwds): def _replace(self, **kwds):
'Return a new Point object replacing specified fields with new values' 'Return a new Point object replacing specified fields with new values'

10
Lib/collections.py
View file

@ -7,7 +7,6 @@ __all__ += _abcoll.__all__
from _collections import deque, defaultdict from _collections import deque, defaultdict
from operator import itemgetter as _itemgetter from operator import itemgetter as _itemgetter
from itertools import izip as _izip
from keyword import iskeyword as _iskeyword from keyword import iskeyword as _iskeyword
import sys as _sys import sys as _sys
@ -18,7 +17,7 @@ def namedtuple(typename, field_names, verbose=False):
>>> Point.__doc__ # docstring for the new class >>> Point.__doc__ # docstring for the new class
'Point(x, y)' 'Point(x, y)'
>>> p = Point(11, y=22) # instantiate with positional args or keywords >>> p = Point(11, y=22) # instantiate with positional args or keywords
>>> p[0] + p[1] # indexable like a plain tuple: (11, 22) >>> p[0] + p[1] # indexable like a plain tuple
33 33
>>> x, y = p # unpack like a regular tuple >>> x, y = p # unpack like a regular tuple
>>> x, y >>> x, y
@ -57,6 +56,7 @@ def namedtuple(typename, field_names, verbose=False):
# Create and fill-in the class template # Create and fill-in the class template
argtxt = repr(field_names).replace("'", "")[1:-1] # tuple repr without parens or quotes argtxt = repr(field_names).replace("'", "")[1:-1] # tuple repr without parens or quotes
reprtxt = ', '.join('%s=%%r' % name for name in field_names) reprtxt = ', '.join('%s=%%r' % name for name in field_names)
dicttxt = ', '.join('%r: t[%d]' % (name, pos) for pos, name in enumerate(field_names))
template = '''class %(typename)s(tuple): template = '''class %(typename)s(tuple):
'%(typename)s(%(argtxt)s)' \n '%(typename)s(%(argtxt)s)' \n
__slots__ = () \n __slots__ = () \n
@ -64,9 +64,9 @@ def namedtuple(typename, field_names, verbose=False):
return tuple.__new__(cls, (%(argtxt)s)) \n return tuple.__new__(cls, (%(argtxt)s)) \n
def __repr__(self): def __repr__(self):
return '%(typename)s(%(reprtxt)s)' %% self \n return '%(typename)s(%(reprtxt)s)' %% self \n
def _asdict(self, dict=dict, zip=zip): def _asdict(t):
'Return a new dict which maps field names to their values' 'Return a new dict which maps field names to their values'
return dict(zip(%(field_names)r, self)) \n return {%(dicttxt)s} \n
def _replace(self, **kwds): def _replace(self, **kwds):
'Return a new %(typename)s object replacing specified fields with new values' 'Return a new %(typename)s object replacing specified fields with new values'
return %(typename)s(*map(kwds.get, %(field_names)r, self)) \n return %(typename)s(*map(kwds.get, %(field_names)r, self)) \n
@ -79,7 +79,7 @@ def namedtuple(typename, field_names, verbose=False):
print template print template
# Execute the template string in a temporary namespace # Execute the template string in a temporary namespace
namespace = dict(itemgetter=_itemgetter, zip=_izip) namespace = dict(itemgetter=_itemgetter)
try: try:
exec template in namespace exec template in namespace
except SyntaxError, e: except SyntaxError, e: