As an example, consider a window in a windowing system. To allow scrolling of the window's contents, one may wish to add horizontal or vertical scrollbars to it, as appropriate. Assume windows are represented by instances of the Window interface, and assume this class has no functionality for adding scrollbars. One could create a subclass ScrollingWindow that provides them, or create a ScrollingWindowDecorator that adds this functionality to existing Window objects. At this point, either solution would be fine.
Did you get it? We just applied the previously learned principles. This is exactly what the decorators do in Python! They wrap a function and modify its behaviour in one way or the another. Now you might be wondering that we did not use the @ anywhere in our code? That is just a short way of making up a decorated function. Here is how we could have run the previous code sample using @.
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:
NOTE  A Property Descriptor is not provided as an argument to a property decorator due to how property decorators are initialized in TypeScript. This is because there is currently no mechanism to describe an instance property when defining members of a prototype, and no way to observe or modify the initializer for a property. The return value is ignored too. As such, a property decorator can only be used to observe that a property of a specific name has been declared for a class.

Using functions with "action-at-a-distance" through sys.settraceback may be okay for an obscure feature that can't be had any other way yet doesn't merit changes to the language, but that's not the situation for decorators. The widely held view here is that decorators need to be added as a syntactic feature to avoid the problems with the postfix notation used in 2.2 and 2.3. Decorators are slated to be an important new language feature and their design needs to be forward-looking, not constrained by what can be implemented in 2.3.

A still life is a work of art depicting mostly inanimate subject matter, typically commonplace objects—which may be either natural (food, flowers, plants, rocks, or shells) or man-made (drinking glasses, books, vases, jewelry, coins, pipes, and so on). With origins in the Middle Ages and Ancient Greek/Roman art, still life paintings give the artist more leeway in the arrangement of design elements within a composition than do paintings of other types of subjects such as landscape or portraiture. Still life paintings, particularly before 1700, often contained religious and allegorical symbolism relating to the objects depicted. Some modern still life breaks the two-dimensional barrier and employs three-dimensional mixed media, and uses found objects, photography, computer graphics, as well as video and sound.
None of these alternatives gained much traction. The alternatives which involve square brackets only serve to make it obvious that the decorator construct is not a list. They do nothing to make parsing any easier. The '<...>' alternative presents parsing problems because '<' and '>' already parse as un-paired. They present a further parsing ambiguity because a right angle bracket might be a greater than symbol instead of a closer for the decorators.

Painters deal practically with pigments,[6] so "blue" for a painter can be any of the blues: phthalocyanine blue, Prussian blue, indigo, Cobalt blue, ultramarine, and so on. Psychological and symbolical meanings of color are not, strictly speaking, means of painting. Colors only add to the potential, derived context of meanings, and because of this, the perception of a painting is highly subjective. The analogy with music is quite clear—sound in music (like a C note) is analogous to "light" in painting, "shades" to dynamics, and "coloration" is to painting as the specific timbre of musical instruments is to music. These elements do not necessarily form a melody (in music) of themselves; rather, they can add different contexts to it.
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