A utility that makes it easy to use dot notation with python dictionaries
Project description
waterbear_is_a_bear
waterbear, A Base Classs That Makes Python Dictionary Accessible With The Dot Notation, Recursively and with Default Values
Now introducing the smallest bear! Waterbear.
Waterbear makes it easy to use python dictionaries with dot notation!
What does Waterbear:bear: do?
Waterbear is like defaultdict + SimpleNameSpace + namedtuples.
Waterbear is similar in usage to namedtuples or recordtypes, but it is not a tuple or array type but a dictionary. The distinction is that Waterbear attributes are accessible via key strings instead of index numbers.
Waterbear is more similar to types.SimpleNamespace. However, a major difference is that Waterbear enables:
setting default values via a default_factory during instantiation
all attributes are recognized by IDE’s static type-checking so they have auto-completion without having to be used first.
work recursively
Now with all of these three, there isn’t an alternative solution available. libraries like Munch has bad support for pythonic idioms. In this case Waterbear allows you to:
use vars(bear) to convert the bear object into a dictionary.
use dict(bear) for the same purpose
use print(bear) and get a dictionary string
… all methods that are available in a python dict object
TODOs
[ ] fix class extension usage pattern
[ ] [STRIKEOUT:merge python2.7 version with python3]
[ ] [STRIKEOUT:make another package called tardigrade]
Installation
pip install waterbear
Usage
For more usage examples, take a look at the test.py!
There are two classes, the Bear and the DefaultBear. Default Bear allows you to pass in a default factory as the first argument. Bear allows you do do so via a keyword argument __default
Example usage below:
# Waterbear is a bear!
from waterbear import Bear
waterbear = Bear(**{"key": 100})
assert waterbear.key == 100, 'now waterbear.key is accessible!'
assert waterbear['key'] == 100, 'item access syntax is also supported!'
Similar to collection.defaultdict, there is DefaultBear
bear = DefaultBear(None, a=10, b=100)
assert vars(bear) == {'a': 10, 'b': 100}
assert bear.does_not_exist is None, "default value works"
DefaultBear like defaultdict
You can use the DefaultBear class and pass in a default factor as the first parameter.
bear = DefaultBear(tuple, a=10, b=100)
assert bear.does_not_exist is (), "default factory also works!"
You can also use it with vars, str, print(repr), dict etc.
bear = Bear(a=10, b=100)
assert str(bear) == "{'a': 10, 'b': 100}"
assert dir(bear) == ['a', 'b']
assert list(iter(bear)) == ['a', 'b']
assert dict(bear) == {'a': 10, 'b': 100}
As Bool in Condition Logic
When used in conditional logic, Bear and DefaultBear behaves exactly like an ordinary dictionary!
def test_dict_comparison():
bear = Bear()
assert not {}, 'empty dictionary are treated as False value.'
assert not bear, 'bear should be treated as False value too!'
Using with Pickle
When using with default factories, only non-callables are picklable.
def test_pickle_setstate_getstate():
# create a default bear with a default factory
bear = DefaultBear('hey', a=10, b=100)
pickle_string = pickle.dumps(bear)
bear_reborn = pickle.loads(pickle_string)
assert type(bear_reborn) == DefaultBear
assert vars(bear_reborn) == {'a': 10, 'b': 100}
bear = DefaultBear(lambda: 'hey', a=10, b=100)
function_fails = False
try:
pickle.dumps(bear)
except AttributeError as e:
function_fails = True
assert function_fails
Using deepcopy
You can just do copy.deepcopy(bear)!
def test_deepcopy():
from copy import deepcopy
original = Bear(a=1, b={'ha': 0})
copy = deepcopy(original)
copy.b.ha += 1
assert copy.b.ha == 1
assert original.b.ha == 0
As A Base Class
Waterbear is completely rewritten to play well with class extension!
class ExtendBear(Bear):
@property
def _hidden_stuff(self):
return "._hidden_stuff"
@property
def __mangled_stuff(self):
return ".__mangled_stuff"
@property
def __dict__(self):
return ".__dict__"
e = ExtendBear()
assert e.__dict__ == ".__dict__"
assert e._hidden_stuff == '._hidden_stuff'
assert e._ExtendBear__mangled_stuff == ".__mangled_stuff"
More Usages Could Be Found in The Tests!
For more usage examples, take a look at test.py.
test_dict = {
'a': 0,
'b': 1
}
# Use spread operators to construct with a dictionary!
test_args = Bear(**test_dict)
assert test_args.a == 0
assert test_args.b == 1
# the value should now be accessible through the key name.
test_args.haha = 0
assert test_args.haha == 0
# You can also use a nested dictionary.
test_args.haha = {'a': 1}
assert test_args.haha != {'a': 1}
assert vars(test_args.haha) == {'a': 1}
assert test_args.haha.a == 1
assert test_args.__dict__['haha']['a'] == 1
assert vars(test_args)['haha']['a'] == 1
assert str(test_args) == "{'a': 0, 'b': 1, 'haha': {'a': 1}}", \
'test_args should be this value "{\'a\': 0, \'b\': 1, \'haha\': {\'a\': 1}}"'
# To set recursion to false, use this `__recursive` parameter.
test_args = Bear(__recursive=False, **test_dict)
assert test_args.__is_recursive == False
assert test_args.a == 0
assert test_args.b == 1
test_args.haha = {'a': 1}
assert test_args.haha['a'] == 1
assert test_args.haha == {'a': 1}
# Some other usage patterns
test_args = Bear(**test_dict, **{'ha': 'ha', 'no': 'no'})
assert test_args.ha == 'ha', 'key ha should be ha'
To Develop
git clone https://github.com/episodeyang/waterbear.git
cd waterbear
make dev
This make dev command should build the wheel and install it in your current python environment. Take a look at the https://github.com/episodeyang/waterbear/blob/master/Makefile for details.
To publish, first update the version number, then do:
make publish
* image credit goes to BBC waterbear: The Smallest
Bear!
😛
Project details
Release history Release notifications | RSS feed
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.
Source Distributions
Built Distribution
Hashes for waterbear-2.4.0-py3-none-any.whl
Algorithm | Hash digest | |
---|---|---|
SHA256 | cc5e7f2d12064a7ae4e2341259164c6f06596884892bd5b969edde326b3e9e00 |
|
MD5 | 63d37e9da17ef76fc0bb418aea20bf00 |
|
BLAKE2b-256 | 6cbb8a030153caca27a44bb6cf631328c6fcf9a9c3896dbb7ddda5090c05062d |