Why use triple-equal (===) in TypeScript? - Stack Overflow
Jul 20, 2019 · JavaScript as the target of compilation (TypeScript design goal 4) All TypeScript must be representable in JavaScript. Further, it should be idiomatic JavaScript where possible. …
Does Typescript support the ?. operator? (And, what's it called?)
Jan 17, 2017 · 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 …
In TypeScript, what is the ! (exclamation mark / bang) operator …
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 …
What is TypeScript and why should I use it instead of JavaScript ...
TypeScript is a superset of the JavaScript language that has a single open-source compiler and is developed mainly by a single vendor: Microsoft. The goal of TypeScript is to help catch …
typescript - 'unknown' vs. 'any' - Stack Overflow
Jul 20, 2018 · TypeScript 3.0 introduces unknown type, according to their wiki: unknown is now a reserved type name, as it is now a built-in type. Depending on your intended use of unknown, …
What does the ampersand (&) mean in a TypeScript type definition?
"Intersection" refers to the resulting type, not the operation performed on the properties.An object belonging to both Type A and Type B must have all properties in A (so that it is an instance of …
What does the `is` keyword do in typescript? - Stack Overflow
So by using the type guard, typescript now knows whether the pet is a Fish or Bird, so the corresponding APIs can be called without any design time linting errors. If it is "Super Critical" …
How do I dynamically assign properties to an object in TypeScript ...
TypeScript is used to catch (potential) errors at compile time. If you cast to any to mute errors then you lose the power of typing and may as well go back to pure JS. any should ideally only …
Interfaces vs Types in TypeScript - Stack Overflow
Update March 2021: The newer TypeScript Handbook (also mentioned in nju-clc answer below) has a section Interfaces vs. Type Aliases which explains the differences. Original Answer …
typescript - How to implement class constants? - Stack Overflow
@Esko I believe that in typescript the const is limited to the file because each file is a module. To make it accessible outside, you would need to declare it with export const and then import it …