Allegory is a figurative mode of representation conveying meaning other than the literal. Allegory communicates its message by means of symbolic figures, actions or symbolic representation. Allegory is generally treated as a figure of rhetoric, but an allegory does not have to be expressed in language: it may be addressed to the eye, and is often found in realistic painting. An example of a simple visual allegory is the image of the grim reaper. Viewers understand that the image of the grim reaper is a symbolic representation of death.
After 2.4a2 was released, in response to community reaction, Guido stated that he'd re-examine a community proposal, if the community could come up with a community consensus, a decent proposal, and an implementation. After an amazing number of posts, collecting a vast number of alternatives in the Python wiki [18], a community consensus emerged (below). Guido subsequently rejected [22] this alternate form, but added:
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.
Enamels are made by painting a substrate, typically metal, with powdered glass; minerals called color oxides provide coloration. After firing at a temperature of 750–850 degrees Celsius (1380–1560 degrees Fahrenheit), the result is a fused lamination of glass and metal. Unlike most painted techniques, the surface can be handled and wetted Enamels have traditionally been used for decoration of precious objects,[22] but have also been used for other purposes. Limoges enamel was the leading centre of Renaissance enamel painting, with small religious and mythological scenes in decorated surrounds, on plaques or objects such as salts or caskets. In the 18th century, enamel painting enjoyed a vogue in Europe, especially as a medium for portrait miniatures.[23] In the late 20th century, the technique of porcelain enamel on metal has been used as a durable medium for outdoor murals.[24]
... the keyword starting the line that heads a block draws a lot of attention to it. This is true for "if", "while", "for", "try", "def" and "class". But the "using" keyword (or any other keyword in its place) doesn't deserve that attention; the emphasis should be on the decorator or decorators inside the suite, since those are the important modifiers to the function definition that follows. ...

The primary objection to this form is that it requires "peeking inside" the method body to determine the decorators. In addition, even though the code is inside the method body, it is not executed when the method is run. Guido felt that docstrings were not a good counter-example, and that it was quite possible that a 'docstring' decorator could help move the docstring to outside the function body.

Painters prepare surfaces of building and other structures and then apply paint by means of brushes, rollers or sprayers. They work with varnish, enamels, lacquer and other materials. They may also paint interior rooms or cover walls with paper, fabrics, vinyls or other materials (paperhanger). They must be able to mix paints as well as do sandblasting and waterblasting.
This code works for our purposes but it’s not exactly dynamic. If we wanted our initial simpleMsg object to sometimes act excited and sometimes quizzical, we could only do so by instantiating entirely new objects from the relevant subclass. Moreover, the ExcitedAndQuizzicalMessage is really just a combination of ExcitedMessage and QuizzicalMessage and probably shouldn’t have its own class. To fix these problems, let’s now return to the decorator pattern and see how it might help us.
Peter Heller is the best-selling author of The Dog Stars. He holds an MFA from the Iowa Writers’ Workshop in both fiction and poetry. An award-winning adventure writer and a longtime contributor to NPR, Heller is a contributing editor at Outside magazine, Men’s Journal, and National Geographic Adventure, and a regular contributor to Bloomberg Businessweek. He is also the author of several nonfiction books, including Kook, The Whale Warriors, and Hell or High Water: Surviving Tibet’s Tsangpo River. He lives in Denver, Colorado.
In a previous article, we discussed how to use the strategy pattern to dynamically change an object’s behavior at runtime. Classically, polymorphism in object-oriented design is static and achieved through inheritance; however, with the strategy pattern you can accomplish the same goal dynamically. Indeed, this is an excellent way to handle situations when you need an object to exhibit different behavior at different times. However, it’s worth noting that the strategy pattern requires mutation of the object you’re working with. By using the strategy pattern, you are necessarily changing the algorithm that an object uses for a given behavior. In some situations, it may be preferable not to mutate a given object. Or more likely, you won’t even have the option of mutating an object because it may come from a codebase over which you have no control (such as an external library). Such cases are relatively common; however, it’s still possible to enhance an immutable object’s behavior. One effective means to do so is with the decorator pattern.
Modern and Contemporary Art has moved away from the historic value of craft and documentation in favour of concept, leading some to say, in the 1960s, that painting as a serious art form is dead.[clarification needed] This has not deterred the majority of living painters from continuing to practice painting either as whole or part of their work. The vitality and versatility of painting in the 21st century defies the previous "declarations" of its demise. In an epoch characterized by the idea of pluralism, there is no consensus as to a representative style of the age. Artists continue to make important works of art in a wide variety of styles and aesthetic temperaments—their merits are left to the public and the marketplace to judge.
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