Understanding TypeScript Features

TypeScript is a popular superset of JavaScript, developed by Microsoft, that adds static types to the language. This feature helps developers to write code that is more understandable and maintainable. TypeScript has several features backported from ECMAScript, such as arrows (arrow functions), classes, and modules.

The question refers to these advanced features and asks which one is not backported to TypeScript. The correct answer is "Methods."

What are TypeScript Methods?

"Methods" in TypeScript refer to functions that are associated with a particular object. They are another way to include behaviour as part of a data structure, providing a clear way to perform actions that directly relate to the object.

While JavaScript and subsequently TypeScript support methods, it's crucial to note that there aren't any unique TypeScript enhancements related to methods that could be considered "backported."

Features like Arrows, Classes, and Modules

On the contrary, features like arrows, classes, and modules were newer JavaScript (ECMAScript) features that TypeScript included and expanded upon, hence considered as "backported."

Arrow functions (=>) in TypeScript are much like lambdas in other languages, capturing the this keyword from the surrounding code.

Classes in TypeScript are an enhancement of ES6/ES2015 classes, providing a cleaner syntax for object-oriented programming and encapsulating data and behaviour into reusable constructs.

Finally, modules in TypeScript are an extension of ES6 modules, allowing developers to split code into separate, reusable parts which can be imported and exported from one another.

Best Practices Using TypeScript

TypeScript has provided developers with a set of powerful tools to write safe, robust, and maintainable code. However, it's crucial to maintain good practices, such as proper use of types, relevant usage of classes and interfaces, and avoiding the use of any type as much as possible.

To go a step further, developers can make use of TypeScript's strict mode, which applies a stricter set of type checking rules and helps catch more potential issues during compile-time, making your code even safer and more robust.

In conclusion, while TypeScript has many ESP features backported into it, "methods" are not one of them, as they exist in JavaScript in their basic form without any specific TypeScript enhancements.