In object-oriented programming, the decorator pattern is a design pattern that allows behavior to be added to an individual object, dynamically, without affecting the behavior of other objects from the same class.[1] The decorator pattern is often useful for adhering to the Single Responsibility Principle, as it allows functionality to be divided between classes with unique areas of concern.[2] The decorator pattern is structurally nearly identical to the chain of responsibility pattern, the difference being that in a chain of responsibility, exactly one of the classes handles the request, while for the decorator, all classes handle the request.
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.

In general, functions in Python may also have side effects rather than just turning an input into an output. The print() function is a basic example of this: it returns None while having the side effect of outputting something to the console. However, to understand decorators, it is enough to think about functions as something that turns given arguments into a value.
Rhythm is important in painting as it is in music. If one defines rhythm as "a pause incorporated into a sequence", then there can be rhythm in paintings. These pauses allow creative force to intervene and add new creations—form, melody, coloration. The distribution of form, or any kind of information is of crucial importance in the given work of art, and it directly affects the aesthetic value of that work. This is because the aesthetical value is functionality dependent, i.e. the freedom (of movement) of perception is perceived as beauty. Free flow of energy, in art as well as in other forms of "techne", directly contributes to the aesthetical value.
Where The Dog Stars established Heller as a writer with a consistent, wickedly humorous voice, a formidable scene setter, and writer with philosophical underpinnings, this second novel shows those strengths fraying a bit. He’s adopting a voice here that isn’t always his own; he toys with the sentence structures of Hemingway and Raymond Carver, and the effect is a bit clumsy. However in the book’s second half he returns to vestiges of his first novel’s voice, and this is where his story becomes compelling.
Syntactic constraints. Python is a syntactically simple language with fairly strong constraints on what can and can't be done without "messing things up" (both visually and with regards to the language parser). There's no obvious way to structure this information so that people new to the concept will think, "Oh yeah, I know what you're doing." The best that seems possible is to keep new users from creating a wildly incorrect mental model of what the syntax means.
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.
The oldest known paintings are at the Grotte Chauvet in France, which some historians believe are about 32,000 years old. They are engraved and painted using red ochre and black pigment, and they show horses, rhinoceros, lions, buffalo, mammoth, abstract designs and what are possibly partial human figures. However, the earliest evidence of the act of painting has been discovered in two rock-shelters in Arnhem Land, in northern Australia. In the lowest layer of material at these sites, there are used pieces of ochre estimated to be 60,000 years old. Archaeologists have also found a fragment of rock painting preserved in a limestone rock-shelter in the Kimberley region of North-Western Australia, that is dated 40,000 years old.[7] There are examples of cave paintings all over the world—in Italy, France, Spain, Portugal, China, Australia, Mexico,[8] etc. In Western cultures, oil painting and watercolor painting have rich and complex traditions in style and subject matter. In the East, ink and color ink historically predominated the choice of media, with equally rich and complex traditions.
Some commonly used decorators that are even built-ins in Python are @classmethod, @staticmethod, and @property. The @classmethod and @staticmethod decorators are used to define methods inside a class namespace that are not connected to a particular instance of that class. The @property decorator is used to customize getters and setters for class attributes. Expand the box below for an example using these decorators.
In general, functions in Python may also have side effects rather than just turning an input into an output. The print() function is a basic example of this: it returns None while having the side effect of outputting something to the console. However, to understand decorators, it is enough to think about functions as something that turns given arguments into a value.

Syntactic constraints. Python is a syntactically simple language with fairly strong constraints on what can and can't be done without "messing things up" (both visually and with regards to the language parser). There's no obvious way to structure this information so that people new to the concept will think, "Oh yeah, I know what you're doing." The best that seems possible is to keep new users from creating a wildly incorrect mental model of what the syntax means.
A figure painting is a work of art in any of the painting media with the primary subject being the human figure, whether clothed or nude. Figure painting may also refer to the activity of creating such a work. The human figure has been one of the contrast subjects of art since the first stone age cave paintings, and has been reinterpreted in various styles throughout history.[38] Some artists well known for figure painting are Peter Paul Rubens, Edgar Degas, and Édouard Manet.
Water miscible oil paints (also called "water soluble" or "water-mixable") is a modern variety of oil paint engineered to be thinned and cleaned up with water, rather than having to use chemicals such as turpentine. It can be mixed and applied using the same techniques as traditional oil-based paint, but while still wet it can be effectively removed from brushes, palettes, and rags with ordinary soap and water. Its water solubility comes from the use of an oil medium in which one end of the molecule has been altered to bind loosely to water molecules, as in a solution.
- [John] When digital artists create expressive art, they tend to reach for a Corel Painter. Painter has a 27-year history of advancing what is possible on the digital canvas and continues to forge new ground. The latest 2019 edition featured here takes a short breather from brush-related features and concentrates on usability and workflow with a complete interface redesign. We'll highlight the new interface by taking on the assignment of creating five travel posters celebrating the great state of California.

In Python 2.4a3 (to be released this Thursday), everything remains as currently in CVS. For 2.4b1, I will consider a change of @ to some other single character, even though I think that @ has the advantage of being the same character used by a similar feature in Java. It's been argued that it's not quite the same, since @ in Java is used for attributes that don't change semantics. But Python's dynamic nature makes that its syntactic elements never mean quite the same thing as similar constructs in other languages, and there is definitely significant overlap. Regarding the impact on 3rd party tools: IPython's author doesn't think there's going to be much impact; Leo's author has said that Leo will survive (although it will cause him and his users some transitional pain). I actually expect that picking a character that's already used elsewhere in Python's syntax might be harder for external tools to adapt to, since parsing will have to be more subtle in that case. But I'm frankly undecided, so there's some wiggle room here. I don't want to consider further syntactic alternatives at this point: the buck has to stop at some point, everyone has had their say, and the show must go on.


There is general agreement that syntactic support is desirable to the current state of affairs. Guido mentioned syntactic support for decorators [2] in his DevDay keynote presentation at the 10th Python Conference [3], though he later said [5] it was only one of several extensions he proposed there "semi-jokingly". Michael Hudson raised the topic [4] on python-dev shortly after the conference, attributing the initial bracketed syntax to an earlier proposal on comp.lang.python by Gareth McCaughan [6].
Writing a class decorator is very similar to writing a function decorator. The only difference is that the decorator will receive a class and not a function as an argument. In fact, all the decorators you saw above will work as class decorators. When you are using them on a class instead of a function, their effect might not be what you want. In the following example, the @timer decorator is applied to a class:
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.

Note that greet_bob(say_hello) refers to two functions, but in different ways: greet_bob() and say_hello. The say_hello function is named without parentheses. This means that only a reference to the function is passed. The function is not executed. The greet_bob() function, on the other hand, is written with parentheses, so it will be called as usual.


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]


We are looking for a Maintenance Operative for a brand new residential development in Southall. Full of gardens, parks, trees and water; this contemporary development is a vibrant place to work with a brilliant team of people. As Maintenance Operative you will ensure the site is well maintained providing a clean and secure environment for residents and guests at all times. Supporting the Development Manager you will keep Health & Safety standards to a maximum. Must have a full clean driving license (to operate the estate vehicle) and Construction Skills Certification Scheme (CSCS) card. Our client is one of the UK's leading residential property management companies. They are a professional and creative employer who really put their people's best interests first. Always looking for the best ideas and solutions to look after people, their homes and communities; you'll be a valued member of this lovely company. Key responsibilities: Provide general maintenance support to the Development Liaise with and provide access to authorised contractors and tradesmen Report defects / incidents (either observed or reported) and take the corrective action Carry out monthly emergency light system checks and ensure monthly fire alarm checks are undertaken with Development Manager Maintain accurate records of maintenance / lighting issues Undertake any routine general repairs /
Aerosol paint (also called spray paint) is a type of paint that comes in a sealed pressurized container and is released in a fine spray mist when depressing a valve button. A form of spray painting, aerosol paint leaves a smooth, evenly coated surface. Standard sized cans are portable, inexpensive and easy to store. Aerosol primer can be applied directly to bare metal and many plastics.
Maintenance Assistant - New Hotel Opening! - Covent Garden Nadler hotels is preparing to open it’s 5 th Hotel in one of the best locations in London – just 2 minutes’ walk away from the world famous Covent Garden. Nadler has an impressive track record for guest satisfaction – being in the top 5% on Tripadvisor in all of the current hotels – Kensington, Soho, Victoria, and Liverpool, and was the winner of Best Small Group Hotel Employer at the Caterer.com Hospitality Awards. We are looking for the best service professionals in the industry to join our growing group to contribute and share in our success. Each of our hotels offers a range of intelligent and extremely comfortable rooms, equipped with a host of features including ultra-fast Wi-Fi, interactive TVs, high quality pocket-sprung beds, spacious bathrooms with powerful showers, and bespoke in-room mini kitchens. Whilst all of this already impresses our guests – It’s our people who turn a good stay into an excellent one! So if you are one of the best, and want to work with like-minded people – apply now! The role What we ask for…. Great communication ski
The Crowne Plaza London Kings Cross has recently completed its exciting journey to emerge as the newest Crowne Plaza hotel in London following a multi-million pound refurbishment and re-branding from Holiday Inn. Our hotel has 429 newly designed bedrooms, the first franchised Belgo Restaurant and the Bloom Bar & Kitchen, which opened a few months ago. The hotel also has 6 state of the art Meeting & Event spaces, a Club Lounge and a Leisure Club. A new opportunity has arisen for the position of Maintenance Shift Engineer. This position would suit a multi-skilled, hands-on, motivated and hard-working individual looking to develop. A person should be adaptable, flexible and able to work both independently and with the team. Experience within the hotel industry and Maintenance/Engineering is desirable but not critically essential. Ideally the candidate will have electrical, mechanical, carpentry, plumbing and decorating/tiling skills and a reasonable working knowledge of stringent PPM of automated plant equipment and general building maintenance. A good level of English is essential. Key responsibilities -Report to the Maintenance Supervisor before your shift starts to go through your daily tasks. -Promptly and efficiently attends and inspects all maintenance requests, defects or Health & Safety matters su

A painter and decorator works with homeowners and commercial business managers to design and create a color/decoration scheme for homes and businesses. This usually means talking with a client to determine particular likes and dislikes in regard to interior design and decoration, making suggestions, and creating an overall project plan that meets the needs of the client. Some clients have clear ideas for their project, while others may want the painter to take the lead and be responsible for developing overall themes and designs. Either way, the position requires considerable experience with interior design, excellent decoration and aesthetic skills, and knowledge of materials and techniques.
Fresco is any of several related mural painting types, done on plaster on walls or ceilings. The word fresco comes from the Italian word affresco [afˈfresːko], which derives from the Latin word for fresh. Frescoes were often made during the Renaissance and other early time periods. Buon fresco technique consists of painting in pigment mixed with water on a thin layer of wet, fresh lime mortar or plaster, for which the Italian word for plaster, intonaco, is used. A secco painting, in contrast, is done on dry plaster (secco is "dry" in Italian). The pigments require a binding medium, such as egg (tempera), glue or oil to attach the pigment to the wall.
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