What is this syntax?

Question

JavaScript

Good afternoon!
There is a function: https://jsfiddle.net/3drhqapa/
Returns a promise.
I did it as in the tutorial: https://learn.javascript.ru/promise#promise-resolv...
The thing is, here is this piece of code:

video_get('-648623423','').then(
        response    => {console.log("Success" + response)},
        error       => {console.log("ERROR:" + error)}
    );

My PHPStorm highlights and says: This inspection reports expression statements which are not assignments or calls. Such statements have no dubious semantics, are normally the result of programmer error.
What does this mean and how to fix it?

Answer 1

This is most likely babel, after compilation the output will be:

video_get('-64866375', '').then(function (response) {
        console.log("Success" + response);
}, function (error) {
        console.log("ERROR:" + error);
});

here is the link to the REPL

Answer 2

This is the syntax of ECMAScript 2015. I think you have everything written correctly: then() takes two arguments, the first of which is a function that will be executed if the promise is fulfilled, and the second is a function that will be executed if an error occurs. The functions are given as arrows. This construct even works: it tells me that an error has occurred, because $http does not exist.
Maybe PHPStorm thinks it's bad when the anonymous function is not immediately executed and passed to some variable. Look here , it seems to me there is the same kind of error.
In general, this is not even an error, but a warning, isn't it? You can actually score on it.