py-pizza-utils

My personal python utilities

Testing

All tests are located in the tests/ directory and use the unittest module

Installation

pip install git+https://github.com/ILikePizza555/py-pizza-utils

Documentation

Iterutils

A collection of utilities for iteration

iterutils.sliding(iterable, size, fillvalue=None)

Creates a sliding iterator of size size for the given iterable. fillvalue specifies the value to return when the iterable runs out of items.

iterutils.map_nested(v, f)

Recursivly applies a function f over a nested data structure v

Stringutils

stringutils.find_from(string, subs, [start, [end]])

Returns a tuple of the lowest index where a substring for string in the iterable subs was found, and the metioned substring. If multiple substrings are found, it will return the first one. If nothing is found, it will return (-1, None)

start and end follows the python slice notation

>>> find_from("abcd", ("d", "c", "b", "a"))
(0, "a")

Listutils

listutils.split(l, index)

Splits a list at the given index. Returns a tuple containing two lists.

listutils.chunk(l, n)

Generator that splits a list into n-sized chunks

Code taken from: https://stackoverflow.com/questions/312443/how-do-you-split-a-list-into-evenly-sized-chunks

Bitfield

A module for dealing with bitfields

class bitfield.Bitfield([value])

Represents a bitfield. This class functions as if the data is little-endian -- that is, the least significant bit is the first one.

An inital value for Bitfield may be passed to the constructor. If none is recieved, the value is 0.

Bitfield supports all binary arithmetic operations: &, ^, |, >>, <<.

Getting bits in a Bitfield is done with the [] operator. When getting bits, if an index is passed, an integer of either 0 or 1 is returned. If a slice is passed, a new Bitfield object holding the selected bits is returned.

>>> b = Bitfield(0b100101)
>>> b[2]
1
>>> b[2:]
Bitfield 0b1001
>>> b[:2]
Bitfield 0b1

Setting bits in a Bitfield is done in a similar manner to lists.

>>> b = Bitfield(0b100101)
>>> b[3] = 1
>>> b
Bitfield 0b101101

Bitfield is iterable. Each bit is a seperator item. It's length is the number of all bits up until the highest set bit.

>>> b = Bitfield(1)
>>> b << 10
Bitfield 0b10000000000
>>> len(b << 10)
11
>>> list(b << 10)
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1]

It is important to note that the length of a bitfield is an implementation detail. Accessing a bit greather than it's Bitfield's length will return 0. Setting a bit greather than it's Bitfield's length will increase the size of the bitfield. Accessing or setting bits using a negative index is untested and unsupported.

Decs

A collection of function decorators.

decs.enforce_state(property_name, expected_value)

A decorator for class member functions.

If the given class property is not equivalent to the expected value when calling the class member, a ValueError will be thrown.

Example

Consider the class:

class Test:
    def __init__(self):
        self.state = 0
        
    @decs.enforce_state("state", 5)
    def member(self):
        pass

Attempting to call member in this state will result in an error:

>>> a = Test()
>>> a.member()
[...]
ValueError: Cannot call member(), state is 0! (Expected: 5)