Python dictionary from an object's fields

Question

Do you know if there is a built-in function to build a dictionary from an arbitrary object? I'd like to do something like this:

>>> class Foo: ...     bar = 'hello' ...     baz = 'world' ... >>> f = Foo() >>> props(f) { 'bar' : 'hello', 'baz' : 'world' } 

NOTE: It should not include methods. Only fields.

Answer 1

Note that best practice in Python 2.7 is to use new-style classes (not needed with Python 3), i.e.

class Foo(object):    ... 

Also, there's a difference between an 'object' and a 'class'. To build a dictionary from an arbitrary object, it's sufficient to use __dict__. Usually, you'll declare your methods at class level and your attributes at instance level, so __dict__ should be fine. For example:

>>> class A(object): ...   def __init__(self): ...     self.b = 1 ...     self.c = 2 ...   def do_nothing(self): ...     pass ... >>> a = A() >>> a.__dict__ {'c': 2, 'b': 1} 

A better approach (suggested by robert in comments) is the builtin vars function:

>>> vars(a) {'c': 2, 'b': 1} 

Alternatively, depending on what you want to do, it might be nice to inherit from dict. Then your class is already a dictionary, and if you want you can override getattr and/or setattr to call through and set the dict. For example:

class Foo(dict):     def __init__(self):         pass     def __getattr__(self, attr):         return self[attr]      # etc...