py_desc

A simple fields descriptors tool for Python

Installation

pip install py-desc

Usage

Simple built-in types

>>> from py_desc.built_in import *
>>>
>>> class YourClass:
...     bool_var = Boolean()
...     string_var = String()
...     positive_int_var = PositiveInteger()
>>>
>>> a = YourClass()
>>> a.positive_int_var = 5
>>> a.string_var = 'str'
>>> a.bool_var = True
>>>
>>> a.bool_var = 'string'
ValueError: Must be boolean
>>> 
>>> a.string_var = 5
ValueError: Must be string
>>> 
>>> a.positive_int_var = -10
ValueError: Cannot be negative

Custom Types

>>> from py_desc.built_in import *
>>>
>>> class YourCustomClass:
...     first = CustomInteger(left=5)
...     second = CustomInteger(right=10)
...     third = CustomInteger(left=1, right=10)
>>>
>>> a = YourClass()
>>> a.first = 2
ValueError: Cannot be smaller than 5
>>> 
>>> a.second = 50
ValueError: Cannot be equal or bigger than 10
>>> 
>>> a.third = 6  # OK. this value in range 1-10
>>> a.third = 12
ValueError: Cannot be not in range [1:10]

>>> from dataclasses import dataclass
>>> from py_desc.built_in import *
>>>
>>> @dataclass
>>> class ExampleData:
...     name: str
...     age: int
>>>
>>>
>>> class YourCustomClass:
...     custom_list_int = CustomList(int)
...     custom_list_data = CustomList(ExampleData)
>>>
>>> a = YourCustomClass()
>>> a.custom_list_int = [5, 6, 3, 6]  # OK. The same type was given
>>> a.custom_list_int = [5.6, 2.1, 'str']
ValueError: Values in list must be int
>>> 
>>> a.custom_list_data = [ExampleData(name='Carl', age=23), ExampleData(name='Daniel', age=21)]
>>> print(a.custom_list_data)
[ExampleData(name='Carl', age=23), ExampleData(name='Daniel', age=21)]
>>> 
>>> a.custom_list_data = (ExampleData(name='Carl', age=23), ExampleData(name='Daniel', age=21))
ValueError: Must be list