Given the following simple class: class Observer { private subscribers: Map<string, Array<((data: any) => void)>> = new Map(); public subscribe(event: string, callback: (data: a...

Code speaks better than language, so: ['a', 'b', 'c'].reduce((accumulator, value) => accumulator.concat(value), []); The code is very silly and returns a copied Array... TS complains on conc...

Consider following code with strictNullChecks turned on: var a: (number | null)[] = [0, 1, 2, 3, null, 4, 5, 6]; var b: { value: number; }[] = a.map(x => x != null && { value: x }).filt...

In TypeScript, if strict null checking is enabled, I would expect the compiler to prevent me from assigning null or undefined values to a variable unless it admits null. However, array access seem...

I have tried to implement strictNullChecks in angular 4 application. I have just added "strictNullChecks": true in tsconfig.json When I run the application ng serve I got this below error. ERROR...