Does Typescript support the ?. operator? (And, what's it called?)
Jan 17, 2017 · Refer to the TypeScript 3.7 release notes for more details. Prior to version 3.7, this was not supported in TypeScript, although it was requested as early as Issue #16 on the TypeScript repo …
In TypeScript, what is the ! (exclamation mark / bang) operator when ...
Feb 16, 2017 · It is explained in the TypeScript release notes: A new ! post-fix expression operator may be used to assert that its operand is non-null and non-undefined in contexts where the type checker …
typescript - Safe navigation operator (?.) or (!.) and null property ...
the operation a! produces a value of the type of a with null and undefined excluded Optional chaining finally made it to typescript (3.7) 🎉 The optional chaining operator ?. permits reading the value of a …
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). When the …
Why use triple-equal (===) in TypeScript? - Stack Overflow
Jul 20, 2019 · Typescript actually does fix == vs === (as far as possible at least). In Javascript there are two comparison operators: == : When comparing primitive values, like numbers and strings, this …
! operator in typescript after object method - Stack Overflow
It's called the "Non-null assertion operator" and it tells the compiler that x.getY() is not null. It's a new typescript 2.0 feature and you can read about it in the what's new page, here's what it says: A new ! …
operator in TypeScript - Stack Overflow
Jul 15, 2020 · The nullish coalescing operator is another upcoming ECMAScript feature that goes hand-in-hand with optional chaining, and which our team has been involved with championing in TC39. …
What does the `in` keyword do in typescript? - Stack Overflow
May 7, 2018 · Edit An alternative meaning of in in typescript is in mapped type definition. You can read about them in the handbook or in the pull request. The in keyword is used there as part of the syntax …
What does the !! (double exclamation mark) operator do in JavaScript?
The !! operator reassures the lint tool that what you wrote is what you meant: do this operation, then take the truth value of the result. A third use is to produce logical XOR and logical XNOR.
What does the TypeScript asserts operator do? - Stack Overflow
Mar 26, 2022 · 3 What does the TypeScript asserts operator do? TypeScript allows you to assert that a certain condition is true, and if it is, the TypeScript type system will narrow the types accordingly in …