pelper - python helper functions

build status coverage read the docs

pelper – python helper functions to ease measuring, ignoring, caching, piping, functional helpers, and more for python 2.7, 3.4, and 3.5.

pelper contains useful helper functions, decorators, context managers - all the things that make your python life a tiny bit easier. pelper has no dependencies, has a coverage of 100%, and is well documented.

Examples

Pipe data through unix-like/elixir-like pipes:

>>> from pelper import pipe
>>> pipe("some datat, some data",
>>>      set,
>>>      (sorted, {"reverse": True}))
['t', 's', 'o', 'm', 'e', 'd', 'a', ',', ' ']

Take n elements from iterables (useful if you can’t use the square bracket notation, e.g., if you’re using pipe)

>>> from pelper import take
>>> take("hello world", 5)
'hello'

Take the n-th elements from iterables (useful if you can’t use the square bracket notation, e.g., if you’re using pipe)

>>> from pelper import nth
>>> nth(range(5), 2)
2

Flatten arbitrarily nested lists:

>>> from pelper import flatten
>>> flatten([1, [2, 2, [3, 3]]])
[1, 2, 2, 3, 3]

Measure the duration of a function:

>>> from pelper import print_duration
>>> @print_duration()
>>> def f(n):
>>>     pass

Measure the duration of a context:

>>> from pelper import print_duration
>>> with print_duration():
>>>     range(4)

Ignore exceptions:

>>> from pelper import ignored
>>> with ignored(OSError):
>>>     raise OSError()  # this is ignored

Cache already computed results of functions:

>>> from pelper import cache
>>> @cache
>>> def fib(n):
>>>     return 1 if n < 2 else fib(n-1) + fib(n-2)
>>> f(500)  # this would run for quite a wile without the cache decorator

Installation

pelper is only one file and has no dependencies. You can simply drop pelper.py into your project and use it.

Or install it from pypi by running:

pip install pelper

Or install it from source by running:

pip install .

Tests

pelper uses doctest extensively and has coverage. You can run the tests with:

python pelper/pelper.py

or:

python -m doctest pelper/pelper.py

or:

python3 pelper/pelper.py

or:

python3 -m doctest pelper/pelper.py

pelper functions

TODO add a list of functions.

TODO generate index etc

Indices and tables