swizzle 0.1.0

Transforms a string representation of a Python literal into the corresponding Python object.

Swizzle Decorator

The Swizzle Decorator for Python enhances attribute lookup methods (__getattr__ or __getattribute__) to facilitate dynamic and flexible retrieval of multiple attributes based on specified arrangements of their names. This concept is reminiscent of swizzling in computer graphics, where it allows efficient access to components of vectors or coordinates in various orders:

import swizzle

@swizzle
class Vector:
    def __init__(self, x, y, z):
        self.x = x
        self.y = y
        self.z = z

print(Vector(1, 2, 3).yzx)  # Output: (2, 3, 1)

Installation

pip install git+https://github.com/janthmueller/swizzle.git

Further Examples

Using swizzle with dataclass

import swizzle
from dataclasses import dataclass

@swizzle
@dataclass
class XYZ:
    x: int
    y: int
    z: int

# Test the swizzle
xyz = XYZ(1, 2, 3)
print(xyz.yzx)  # Output: (2, 3, 1)

Using swizzle with IntEnum

import swizzle
from enum import IntEnum

@swizzle(meta=True)
class XYZ(IntEnum):
    X = 1
    Y = 2
    Z = 3

# Test the swizzle
print(XYZ.yxz)  # Output: (2, 3, 1)

Setting the meta argument to True in the swizzle decorator extends the getattr behavior of the metaclass, enabling attribute swizzling directly on the class itself.

Using swizzle with NamedTuple

import swizzle
from typing import NamedTuple

@swizzle
class XYZ(NamedTuple):
    x: int
    y: int
    z: int

# Test the swizzle
xyz = XYZ(1, 2, 3)
print(xyz.yzx)  # Output: (2, 3, 1)

Sequential matching

Attributes are matched from left to right, starting with the longest substring match.

import swizzle

@swizzle(meta=True)
class Test:
    x = 1
    y = 2
    z = 3
    xy = 4
    yz = 5
    xz = 6
    xyz = 7

# Test the swizzle
print(Test.xz)  # Output: (6,)
print(Test.yz)  # Output: (5,)
print(Test.xyyz)  # Output: (4, 5)
print(Test.xyzx)  # Output: (7, 1)