pprint的定制，ordereddict相关

by windviki

2013/04/24

 

1. pprint无法为OrderedDict正常显示类似dict的层次结构：

In [1]: from collections import OrderedDict

In [2]: import pprint

In [3]: od = OrderedDict([("key1", 100), ("I'm key2", 2), ("a key3", 3)])

In [4]: d = dict([("key1", 100), ("I'm key2", 2), ("a key3", 3)])

In [5]: pprint.pprint(od)
OrderedDict([('key1', 100), ("I'm key2", 2), ('a key3', 3)])

In [6]: pprint.pprint(d)
{"I'm key2": 2, 'a key3': 3, 'key1': 100}

 

2.pprint无法将unicode或者utf8字符正确的显示和打印，总是会format成16进制的格式。

In [7]: od["测试"] = unicode("中文", "utf-8")

In [8]: pprint.pprint(od)
OrderedDict([('key1', 100), ("I'm key2", 2), ('a key3', 3), ('\xe6\xb5\x8b\xe8\xaf\x95', u'\u4e2d\u6587')])

 

3.综上，需要对pprint进行patch才能满足需求。

#*- coding: utf-8 *-
#####################################################################
#    Created:    2012/7/27   13:33
#    Filename:   printod.py
#    Author:     viki
#    Copyright:  
#********************************************************************
#    Comments:    
#
#    UpdateLogs:    
#####################################################################
import os
import sys
import json
import types
from collections import OrderedDict
OrderedDict.__repr__ = dict.__repr__

def _sorted(iterable):
    return iterable

import pprint
pprint._sorted = _sorted

class MyPrettyPrinter(pprint.PrettyPrinter):
    def __init__(self, encoding="utf-8", indent=1, width=80, depth=None, stream=None):
        self._encoding = encoding
        pprint.PrettyPrinter.__init__(self, indent, width, depth, stream)

    def _format(self, object, stream, indent, allowance, context, level):
        if type(object) == types.StringType:
            object = object.decode(self._encoding)
        return pprint.PrettyPrinter._format(self, object, stream, indent, allowance, context, level)

    def format(self, object, context, maxlevels, level):
        if type(object) == types.StringType:
            return ("\"%s\"" % object.decode().encode(self._encoding), True, False)
        if isinstance(object, unicode):
            return ("\"%s\"" % object.encode(self._encoding), True, False)
        return pprint.PrettyPrinter.format(self, object, context, maxlevels, level)

od = OrderedDict([
    ("hello", u"unicode文字"), 
    ("a", "中文2"), 
    ("测试", 3), 
    ("od", OrderedDict([("test2", 1), ("test1第二个keyの", 2)])),
    ("xx", dict([("dict1", 1), ("dict2", u"无序字典"), ("dict3", [1, 2, 3, (4, 100)])])),
    ])

with open("printod.txt", "w+") as fd:
    fd.write("#*- coding: utf-8 *-\n")
    fd.write(MyPrettyPrinter().pformat(od))

来自为知笔记(Wiz)Time=2013-04-24 14:12:34