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 …
What is TypeScript and why should I use it instead of JavaScript?
What is the TypeScript language? What can it do that JavaScript or available libraries cannot do, that would give me reason to consider it?
What does the `is` keyword do in typescript? - Stack Overflow
So by using the type guard, typescript now knows whether the is a or , so the corresponding APIs can be called without any design time linting errors. If it is "Super Critical" for that API to be …
Interfaces vs Types in TypeScript - Stack Overflow
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.
typescript - How can I define an interface for an array of objects ...
Do not use interface EnumServiceGetOrderBy { [index: number]: { id: number; label: string; key: any }; } You will get errors for all the Arrays properties and methods such as splice etc. The …
How to get a variable type in Typescript? - Stack Overflow
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 …
How to run TypeScript files from command line? - Stack Overflow
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, …
TypeScript: Type 'string | undefined' is not assignable to type 'string'
Feb 2, 2019 · Alternatively, you can type name1 as string | undefined, and handle cases of undefined further down. However, it's typically better to handle unexpected errors earlier on. …
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 …
Difference between 'object' , {} and Object in TypeScript
Mar 24, 2018 · TypeScript has three confusing types: {}, Object, and object. You can't assign undefined nor null to any of those types except if the strictNullChecks compiler option is disabled.