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How to design a more flexible and reusable codebase with Python metaclasses and decorators - sample python code
By Guest on 29th December 2022 01:09:58 AM | Syntax: PYTHON | Views: 311


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  1. How can I use Python's advanced object-oriented features, such as metaclasses and decorators, to design a more flexible and reusable codebase?
  2.  
  3. Metaclasses and decorators are advanced object-oriented features in Python that can be used to modify the behavior of classes and methods in a flexible and reusable way. Here is a simple example of how you might use these features to design a more flexible and reusable codebase in Python:
  4.  
  5.  
  6. import functools
  7.  
  8. def cache(func):
  9.    """A decorator that caches the return value of a function."""
  10.    @functools.wraps(func)
  11.    def wrapper(*args, **kwargs):
  12.        key = (args, frozenset(kwargs.items()))
  13.        if key not in wrapper.cache:
  14.            wrapper.cache[key] = func(*args, **kwargs)
  15.        return wrapper.cache[key]
  16.    wrapper.cache = {}
  17.    return wrapper
  18.  
  19. class CachedMeta(type):
  20.    """A metaclass that applies the cache decorator to all methods."""
  21.    def __new__(cls, name, bases, namespace):
  22.        for attr, value in namespace.items():
  23.            if callable(value):
  24.                namespace[attr] = cache(value)
  25.        return type.__new__(cls, name, bases, namespace)
  26.  
  27. class MyClass(metaclass=CachedMeta):
  28.    def slow_method(self, arg):
  29.        # Some slow computation here
  30.        return result
  31.  
  32.  
  33. In this example, the cache decorator is used to cache the return value of a function so that it only needs to be computed once. The CachedMeta metaclass is then used to apply this decorator to all methods in a class, so that all of their return values are automatically cached. This can be a useful way to improve the performance of a class that has many slow methods, without having to manually apply the decorator to each one.
  34.  
  35. Note that this is just a simple example, and there are many other ways that metaclasses and decorators can be used to design a more flexible and reusable codebase in Python. For more information and examples, you may want to consult the Python documentation or other resources on these advanced object-oriented features.
















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