Jul 20, 2019 · In JavaScript, it's commonly seen as best practice to use === instead of ==, for obvious and well-known reasons. In TypeScript, which is one to be preferred? Is there even one which is …

Jan 17, 2017 · Yes. As of TypeScript 3.7 (released on November 5, 2019), this feature is supported and is called Optional Chaining: At its core, optional chaining lets us write code where TypeScript can …

What does the ampersand (&) mean in a TypeScript type definition? Asked 9 years, 4 months ago Modified 1 year ago Viewed 97k times

Feb 16, 2017 · It tells TypeScript to leave the expressions result as it is and pass it to JavaScript. It allows the use of JavaScript semantics in TypeScript, such as using loose equality (with the …

Learn how to dynamically assign properties to an object in TypeScript with this helpful guide.

export function foo(arg: string): arg is MyType { return ... } I haven't been able to search for is in either the docs or google, it's a pretty common word and shows up on basically every page. What does the …

The key aspect to interfaces in typescript that distinguish them from types is that they can be extended with new functionality after they've already been declared.

Feb 22, 2016 · 10 Type guards in typescript To determine the type of a variable after a conditional statement you can use type guards. A type guard in typescript is the following: An expression which …

Jul 26, 2018 · Typescript: Check "typeof" against custom type Asked 7 years, 4 months ago Modified 2 years, 3 months ago Viewed 373k times

Nov 5, 2015 · None of the other answers discuss how to run a TypeScript script that uses modules, and especially modern ES Modules. First off, ts-node doesn't work in that scenario, as of March 2020. So …