A small pure-python package for utility decorators.

.. code-block:: python

from decore import lazy_property

@lazy_property
def paramless_big_calc():
sub_res = [big_func(const) for const in array_of_constants]
return sum(sub_res)

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Installation

Install decore with:

.. code-block:: bash

pip install decore

Decorators

lazy_property

The lazy_property decorator is meant to decorate functions that compute some constant value or property that you only want to compute once. The first call to the decorated function will run it and save the value (in memory) before returning it; subsequent calls will get this value without trigerring the calculation.

You can think about it like a functools.lru_cache(maxsize=1) for functions with no parameters.

.. code-block:: python

from decore import lazy_property

@lazy_property
def paramless_big_calc():
"""I take a lot of time!"""
sub_res = [big_func(const) for const in array_of_constants]
return sum(sub_res)

threadsafe_generator

The threadsafe_generator decorator makes generators threadsafe. This means multiple threads can be given references to the decorated generator and it is guarenteed that each item in the stream will be yielded (i.e. returned) to only a single thread.

.. code-block:: python

from decore import threadsafe_generator

@threadsafe_generator
def user_documents(day):
"""I yield some MongoDB documents!"""
client = get_mongodb_client(some_params)
dt_obj = translate_day_to_dt(day)
user_document_cursor = client.some_mongodb_query(dt_obj, SOME_CONST)
while True:
yield user_document_cursor.next()

Contributing

Package author and current maintainer is Shay Palachy (shay.palachy@gmail.com); You are more than welcome to approach him for help. Contributions are very welcomed.

Installing for development

Clone:

.. code-block:: bash

git clone git@github.com:shaypal5/decore.git

Install in development mode with test dependencies:

.. code-block:: bash

cd decore
pip install -e ".[test]"

Running the tests

To run the tests, use:

.. code-block:: bash

python -m pytest --cov=decore

Adding documentation

This project is documented using the numpy docstring conventions, which were chosen as they are perhaps the most widely-spread conventions that are both supported by common tools such as Sphinx and result in human-readable docstrings (in my personal opinion, of course). When documenting code you add to this project, please follow these conventions.

.. _numpy docstring conventions: https://github.com/numpy/numpy/blob/master/doc/HOWTO_DOCUMENT.rst.txt
.. _these conventions: https://github.com/numpy/numpy/blob/master/doc/HOWTO_DOCUMENT.rst.txt