bunch
bunch copied to clipboard
A Bunch is a Python dictionary that provides attribute-style access (a la JavaScript objects).
bunch
Bunch is a dictionary that supports attribute-style access, a la JavaScript.
>>> b = Bunch()
>>> b.hello = 'world'
>>> b.hello
'world'
>>> b['hello'] += "!"
>>> b.hello
'world!'
>>> b.foo = Bunch(lol=True)
>>> b.foo.lol
True
>>> b.foo is b['foo']
True
Dictionary Methods
A Bunch is a subclass of dict; it supports all the methods a dict does:
>>> b.keys()
['foo', 'hello']
Including update():
>>> b.update({ 'ponies': 'are pretty!' }, hello=42)
>>> print repr(b)
Bunch(foo=Bunch(lol=True), hello=42, ponies='are pretty!')
As well as iteration:
>>> [ (k,b[k]) for k in b ]
[('ponies', 'are pretty!'), ('foo', Bunch(lol=True)), ('hello', 42)]
And "splats":
>>> "The {knights} who say {ni}!".format(**Bunch(knights='lolcats', ni='can haz'))
'The lolcats who say can haz!'
Serialization
Bunches happily and transparently serialize to JSON and YAML.
>>> b = Bunch(foo=Bunch(lol=True), hello=42, ponies='are pretty!')
>>> import json
>>> json.dumps(b)
'{"ponies": "are pretty!", "foo": {"lol": true}, "hello": 42}'
If JSON support is present (json or simplejson), Bunch will have a toJSON() method which returns the object as a JSON string.
If you have PyYAML installed, Bunch attempts to register itself with the various YAML Representers so that Bunches can be transparently dumped and loaded.
>>> b = Bunch(foo=Bunch(lol=True), hello=42, ponies='are pretty!')
>>> import yaml
>>> yaml.dump(b)
'!bunch.Bunch\nfoo: !bunch.Bunch {lol: true}\nhello: 42\nponies: are pretty!\n'
>>> yaml.safe_dump(b)
'foo: {lol: true}\nhello: 42\nponies: are pretty!\n'
In addition, Bunch instances will have a toYAML() method that returns the YAML string using yaml.safe_dump(). This method also replaces __str__ if present, as I find it far more readable. You can revert back to Python's default use of __repr__ with a simple assignment: Bunch.__str__ = Bunch.__repr__. The Bunch class will also have a static method Bunch.fromYAML(), which loads a Bunch out of a YAML string.
Finally, Bunch converts easily and recursively to (unbunchify(), Bunch.toDict()) and from (bunchify(), Bunch.fromDict()) a normal dict, making it easy to cleanly serialize them in other formats.
Miscellaneous
-
It is safe to
import *from this module. You'll get:Bunch,bunchify, andunbunchify. -
Ample doctests
$ python -m bunch.test $ python -m bunch.test -v | tail -n22 1 items had no tests: bunch.fromYAML 16 items passed all tests: 8 tests in bunch 13 tests in bunch.Bunch 7 tests in bunch.Bunch.__contains__ 4 tests in bunch.Bunch.__delattr__ 7 tests in bunch.Bunch.__getattr__ 3 tests in bunch.Bunch.__repr__ 5 tests in bunch.Bunch.__setattr__ 2 tests in bunch.Bunch.fromDict 2 tests in bunch.Bunch.toDict 5 tests in bunch.bunchify 2 tests in bunch.from_yaml 3 tests in bunch.toJSON 6 tests in bunch.toYAML 3 tests in bunch.to_yaml 3 tests in bunch.to_yaml_safe 4 tests in bunch.unbunchify 77 tests in 17 items. 77 passed and 0 failed. Test passed.
Feedback
Open a ticket / fork the project on GitHub, or send me an email at [email protected].