The .__init__() method must store a reference to the function and can do any other necessary initialization. The .__call__() method will be called instead of the decorated function. It does essentially the same thing as the wrapper() function in our earlier examples. Note that you need to use the functools.update_wrapper() function instead of @functools.wraps.
One of the other advantages of the decorator pattern is that wrapped objects can retain the type of the original object. As a result, you can use original and wrapped objects interchangeably, which is a significant advantage when your goal is to write flexible code. In this manner, you can easily extend the behavior of a particular object without modifying the original code.
John Mansell Smith has been a self-employed painter & decorator for four years. He explains what it’s like to run your own business. “I became a self-employed painter & decorator when I took early retirement from my professional job in London, where I was employed as a Principal Building Surveyor. When I retired, I needed some additional income to supplement my pension, and having been in the building industry I was fully aware of the standard and quality which would be required to produce work to a professional standard. For a typical day at work, I usually arrive at the job at 8.30 am, and then depending on the sort of work I am doing it will vary a great deal. I could be undertaking external decorations or internal decorations, but in each case it would require covering and protecting the client's furniture, preparation of surfaces, washing down the walls, painting, wallpapering, cleaning up, etc. I try to leave at about 4.30 pm, but this may vary depending on the stage that I have reached with the job. In terms of likes and dislikes, I don’t enjoy working outside in poor weather, although I try to plan my workload to avoid this. However, I do like the freedom of being my own boss and getting complimented on a good job. If you wanted to be a painter and decorator, you would have to decide whether you wish to work for a company with the benefits such as holiday pay, but with the constraints of not being your own boss, or working for yourself with the freedom this gives but also the uncertainty of workload. As a self-employed person I can charge about £15 per hour for work that I do on an hourly rate, or I base any calculations on this rate when I am producing an estimate for a client. In attempting to find work, I would try the job centre, trade journals, large decorating companies, the internet and building training boards. To do the job you need to be a clean, neat worker with an eye for detail. The job you produce is the final result that the client will see, so it is vital that you can produce a finished job that you would be happy to have in your own home.
When we instantiate a SimpleMessage and then pass it to the various decorators, we now get new behavior. Moreover, since both the concrete component and the concrete decorators all implement / descend from IMessage, they are interchangeable as far as the program is concerned, meaning that we can loop over them together. Further, rather than having to create a new ExcitedAndQuizzicalMessageDecorator class, we were able to achieve the same effect by double wrapping a SimpleMessage object (first in an ExcitedMessageDecorator and then in a QuizzicalMessageDecorator). Finally, note that despite having been passed into various decorators, our simpleMsg object remains unchanged at the end of the program.
The first example of modernism in painting was impressionism, a school of painting that initially focused on work done, not in studios, but outdoors (en plein air). Impressionist paintings demonstrated that human beings do not see objects, but instead see light itself. The school gathered adherents despite internal divisions among its leading practitioners, and became increasingly influential. Initially rejected from the most important commercial show of the time, the government-sponsored Paris Salon, the Impressionists organized yearly group exhibitions in commercial venues during the 1870s and 1880s, timing them to coincide with the official Salon. A significant event of 1863 was the Salon des Refusés, created by Emperor Napoleon III to display all of the paintings rejected by the Paris Salon.
More recently, professional painters are responsible for all preparation prior to painting. All scraping, sanding, wallpaper removal, caulking, drywall or wood repair, patching, stain removal, filling nail holes or any defects with plaster or putty, cleaning, taping, preparation and priming are considered to be done by the professional contracted painter.
This wrapper_repeat() function takes arbitrary arguments and returns the value of the decorated function, func(). This wrapper function also contains the loop that calls the decorated function num_times times. This is no different from the earlier wrapper functions you have seen, except that it is using the num_times parameter that must be supplied from the outside.
You saw that, to define a decorator, you typically define a function returning a wrapper function. The wrapper function uses *args and **kwargs to pass on arguments to the decorated function. If you want your decorator to also take arguments, you need to nest the wrapper function inside another function. In this case, you usually end up with three return statements.
Thanks to enhanced support for multi-core processors and CPUs that use AVX2 extensions and extensive code optimizations, this is the fastest version of Painter yet. A huge selection of brushes are noticeably faster — some as much as twice as fast. You can also take advantage of faster document rendering when zooming, panning and rotating — up to 50% faster.