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6: Decorators     
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Summary
============

- Decorators are functions that take a single function as an argument and return a single function
    - They are used to transform functions
- A decorator is written as @dec in front of a function definition and that is equivalent to f = dec(f) where f is the name of the function
- Some decorators modify the unction by returning a new wrapper function object
- Some decorators add or modify attributes of the function object and do not return a new function object
- Multiple decorators are applied starting with the decorator closest to the function working up the page
- You can also use a decorator factory with parameters
    - It is evaluated at once and has to return a decorator, which is applied to the function in the usual way
- The main use of a decorator factory is to provide parameters to a decorator
- Decorators that return wrappers are more complicated because they change the function object
    - The standard wraps method can be used to transfer attributes from the original function object to the new object

Program
============

.. literalinclude:: programs/chapterSix.py
   :language: python

Program Output
=================

.. code-block:: console

    (docs-env) root@BMitchellLTOP:~/git/sphinx_students/source/programming_lang/book/programs# python3 chapterSix.py
    Calling function: greet
    Hello Alice!
    Hello Alice!

    Function name: greet
    Author attribute: Brayden