What's the deal with the `return of ()` syntax?

Just came across this piece of code:

https://i.sstatic.net/JZXP5.png

Code snippet in typescript. The first line looks like:

... return of (true);

Can someone explain this syntax to me?

Answer №1

This code snippet showcases the use of short function names, most of which are RxJS operators.

For instance:

  • of()
  • from()
  • mergeMap()

These functions are normally invoked with a prefix like "Observable.", but in this case, they are referenced without it for brevity.

If you examine the beginning of the snippet, you'll find the imports for these RxJS operators.

Please note that while this technique may save some typing, it can also make the code more challenging to understand at first glance.

Answer №2

It's probably a function named of that is being passed the value true. The spaces around the parentheses don't matter in this context.

Answer №3

The keyword 'of' is not recognized in TypeScript as it must be part of a function like the one below:


function of<T>(value: T) {
     // ...
}

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