Why use triple-equal (===) in TypeScript? - Stack Overflow
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 …
Does Typescript support the ?. operator? (And, what's it called?)
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 …
When should I use ?? (nullish coalescing) vs || (logical OR)?
The ?? operator was added to TypeScript 3.7 back in November 2019. And more recently, the ?? operator was included in ES2020, which is supported by Node 14 (released in April 2020).
In TypeScript, what is the ! (exclamation mark / bang) operator when ...
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 …
Newest 'typescript' Questions - Stack Overflow
2 days ago · How to correctly type Object.keys() lookup in a JavaScript project with TypeScript type-checking enabled? [duplicate] I am working in a JavaScript project with TypeScript type-checking …
How do I dynamically assign properties to an object in TypeScript ...
Learn how to dynamically assign properties to an object in TypeScript with this helpful guide.
What does the `is` keyword do in typescript? - Stack Overflow
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 …
Interfaces vs Types in TypeScript - Stack Overflow
When creating or maintaining TypeScript definitions for pure JavaScript modules, interfaces should probably be used for everything that is a class in the original module; particularly examples like chai, …
Typescript: Check "typeof" against custom type - Stack Overflow
Jul 26, 2018 · The syntax of TypeScript is such that some expressions and statements refer to values that exist at runtime, while other expressions and statements refer to types that exist only at …
What is the difference Between '!:' and '?:' in TypeScript object ...
Aug 21, 2020 · TypeScript won't warn that lastName is never assigned and assumes its value is a string, when in fact it's not there and so reading its value will result in undefined.