I just found the answer to this in another Stack Overflow question’s answer. declare global { interface Window { MyNamespace: any; } } window.MyNamespace = window.MyNamespace || {}; Basically, you need to extend the existing window interface to tell it about your new property.
That’s the non-null assertion operator. It is a way to tell the compiler “this expression cannot be null or undefined here, so don’t complain about the possibility of it being null or undefined.” Sometimes the type checker is unable to make that determination itself. It is explained here: A new ! post-fix expression operator may … Read more
Exactly like in JavaScript, you can use the parseInt or parseFloat functions, or simply use the unary + operator: var x = “32”; var y: number = +x; All of the mentioned techniques will have correct typing and will correctly parse simple decimal integer strings like “123”, but will behave differently for various other, possibly … Read more
2019 Update The current answers and the official documentation are outdated. And for those new to TypeScript, the terminology used isn’t clear without examples. Below is a list of up-to-date differences. 1. Objects / Functions Both can be used to describe the shape of an object or a function signature. But the syntax differs. Interface … Read more