OrderedDict

python

since 2013-02-10

dict だと for で順番どおりに取り出せない：

files = {
	'DURATION_PDF': ('dur.pdf',),
	'DURATION_TREE': ('tree-dur.inf',),
	'STREAM_WIN[MCP]': ('mgc.win1', 'mgc.win2', 'mgc.win3',),
	}
for key, value in files.iteritems():
	for f in value:
		print 'writing %s' % f

>python dict.py
writing mgc.win1
writing mgc.win2
writing mgc.win3
writing tree-dur.inf
writing dur.pdf

OrderedDict を使うと順番どおりに取り出せる：

from collections import OrderedDict
files = OrderedDict([
		('DURATION_PDF', ('dur.pdf',)),
		('DURATION_TREE', ('tree-dur.inf',)),
		('STREAM_WIN[MCP]', ('mgc.win1', 'mgc.win2', 'mgc.win3',)),
		])
for key, value in files.iteritems():
	for f in value:
		print 'writing %s' % f

>python ordered_dict.py
writing dur.pdf
writing tree-dur.inf
writing mgc.win1
writing mgc.win2
writing mgc.win3