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.
With the introduction of Classes in TypeScript and ES6, there now exist certain scenarios that require additional features to support annotating or modifying classes and class members. Decorators provide a way to add both annotations and a meta-programming syntax for class declarations and members. Decorators are a stage 2 proposal for JavaScript and are available as an experimental feature of TypeScript.
And for the more subtle decorators, there a slew of super-cute displays that are much more low-key. Check out these meddling mice, a simple trick or treat text, or this tribute to Edgar Allan Poe. — Jennifer Aldrich, Country Living, "These Halloween Stair Decals Will Instantly Transform Your Home Into a Haunted House," 7 Oct. 2018 Another fun tidbit for all of you aspiring IRL dorm decorators, Hailey painted all the art featured in her freshman dorm — now, that’s the perfect personal touch. — Katelyn Chef, Teen Vogue, "University of Mississippi Dorm Decor," 23 Aug. 2018 We reporters and bloggers eat family style, at a long table chosen and donated by Rachael Ray (and her decorator). — Grant Cornett, Vogue, "The Rise of Refugee Cuisine—a Food-World Trend to Feel Good About," 17 Aug. 2018 The social media sensation has forced some decorators to think outside the box and get creative with non-edible decorations. — Caroline Judelson, Fox News, "Engagement cookies are the new bridal trend," 9 Aug. 2018 The project took Kime two years, during which time decorator and client became close friends. — David Usborne, Town & Country, "The Mysterious Case of the Parnham House Fire," 29 May 2018 The look, which also can be seen in her other homes, reflects the influence of Gail Melikian, Ms. Rafaelian’s best friend and decorator who owns an antique store in Cranston. — Candace Taylor, WSJ, "Inside the Many, Many Homes of This Jewelry Billionaire," 12 July 2018 Naturally, faux fur also appeals to home decorators who want to stay animal-friendly. — Kelsey Kloss, ELLE Decor, "How To Decorate With Faux Fur, According To Top Designers," 7 Sep. 2016 The 11,821 square feet of living space was designed by former White House decorator Michael Smith and features reclaimed fireplace mantels, hand-hewn hardwood floors and custom ironwork. — Jack Flemming, latimes.com, "Mega-producer Jerry Bruckheimer pulls in $11.5 million for Brentwood estate," 16 June 2018
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.

Painting is an important form in the visual arts, bringing in elements such as drawing, gesture (as in gestural painting), composition, narration (as in narrative art), or abstraction (as in abstract art).[2] Paintings can be naturalistic and representational (as in a still life or landscape painting), photographic, abstract, narrative, symbolistic (as in Symbolist art), emotive (as in Expressionism), or political in nature (as in Artivism).
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