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Python dict using dot notation and chaining

Ideally, I aim to achieve a class that extends (or is very similar) to dictin Python with additional features:

  • Dot-Notation, capable of setting and receiving values
  • Key-Value features like dict(i.e. setitem, getitem)
  • Can cling operations with spot recording.

The goal is that if I have something like example = DotDict()that, I could do the following against him example.configuration.first= 'first', and he will create instances of the corresponding DotDict in examplewith a very painful warning that if the operation is not assigned, it just needs to raise KeyError, like a dictmake

That's what I naively put together

class DotDict(dict):
    def __getattr__(self, key):
        """ Make attempts to lookup by nonexistent attributes also attempt key lookups. """
        import traceback
        import re
        s= ''.join(traceback.format_stack(sys._getframe(1),1))
        if re.match(r'  File.*\n.*[a-zA-Z]+\w*\.[a-zA-Z]+[a-zA-Z0-9_. ]*\s*=\s*[a-zA-Z0-9_.\'"]+',s):
            self[key] = DotDict()
            return self[key]

        return self[key]

    def __setattr__(self, key, value):
        if isinstance(value,dict):
            self[key] = DotDict(value)
        self[key] = value

, , , , . , .

, Python , , a.b.c = 3, - getattr(a,b), setattr, .

, , - , , setattr.

Edit:

, user1320237.

class DotDict(dict):
    def __getattr__(self, key):
        """ Make attempts to lookup by nonexistent attributes also attempt key lookups. """
        if self.has_key(key):
            return self[key]
        import sys
        import dis
        frame = sys._getframe(1)
        if '\x00%c' % dis.opmap['STORE_ATTR'] in frame.f_code.co_code:
            self[key] = DotDict()
            return self[key]

        raise AttributeError('Problem here')

    def __setattr__(self, key, value):
        if isinstance(value,dict):
            self[key] = DotDict(value)
        self[key] = value

, . , STORE_ATTR, , a.b.this.doesnt.exist.yet = 'something' . , CPython.

+3
5

getattribute ,

object.__getattribute__

dis. , , , .

>>> import dis
>>> def g():
    a.b.c = 4


>>> dis.dis(g)
  2           0 LOAD_CONST               1 (4)
              3 LOAD_GLOBAL              0 (a)
              6 LOAD_ATTR                1 (b)
              9 STORE_ATTR               2 (c)
             12 LOAD_CONST               0 (None)
             15 RETURN_VALUE
+3

user1320237 , . , , .

class A(object):
    def __getattribute__(self, attr):
        try:
            return super(A, self).__getattribute__(attr)
        except AttributeError:
            self.__setattr__(attr, A())
            return super(A, self).__getattribute__(attr)
+1

: http://tech.zarmory.com/2013/08/python-putting-dot-in-dict.html

>>> d = DefaultDotDict({1: {2: 3}})
>>> d.a.b.c.d = "magic!"
>>> import json; print json.dumps(d, indent=2)
{
  "a": {
    "b": {
      "c": {
        "d": "magic!"
      }
    }
  }, 
  "1": {
    "2": 3
  }
}
>>>
+1
source

class DotDict (dict):

"""Dot natation for dict"""

def __init__(self, theDict):
    super(MyDict, self).__init__()
    for key, item in theDict.items():
        if isinstance(item, dict):
            item = MyDict(item)
        self.__dict__[key] = item

def __getattr__(self, key):
    return self.__dict__[key]

def __setattr__(self, name, value):
    self.__dict__[name] = value
0
source

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