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Re:Stop writing lambda expressions in Python by joshuamorton on Thursday September 27, 2018 @08:29PM (#18090057)
As a user of JavaScript and es6, fat arrows are only necessary if you haven't started using async and await syntax, and I found myself almost never using fat arrows after moving to async/await.

Indeed naming my functions resulted in more testable and clearer code.

Re:Stop writing lambda expressions in Python by andrewstuart on Thursday September 27, 2018 @09:10PM (#18090243)
Hmmmm. I don't see the relationship between async/await and fat arrows.

Can you explain more about how async/await obviates the need for fat arrows?

Re:Stop writing lambda expressions in Python by joshuamorton on Thursday September 27, 2018 @09:18PM (#18090279)
Just async is callback based.

You don't need callbacks with async/await. No callbacks, no need for fat arrow.

Re:Stop writing lambda expressions in Python by andrewstuart on Friday September 28, 2018 @01:03AM (#18091215)
Interesting idea.
Re:Stop writing lambda expressions in Python by danShumway on Friday September 28, 2018 @02:09PM (#18095598)
Getting rid of fat arrows is one thing, but I use async/await pretty much all the time, and I still use anonymous functions in my code.

  await (async function () {
    //Do a thing
  }());
I don't think async changes anything about how useful or problematic an anonymous function is.
Re:Stop writing lambda expressions in Python by joshuamorton on Friday September 28, 2018 @02:45PM (#18095920)
That feels like a weird pattern (for one because you can have async fat arrows), but also because in general I find

    await request_some_data()
much clearer than

    await (async () => {
        // just make the async request inline
    })()
Re:Stop writing lambda expressions in Python by danShumway on Friday September 28, 2018 @03:15PM (#18096206)
When arrow functions were first released, they didn't support the `async` keyword. I guess that wasn't fixed until ES2018? Maybe earlier - I think Babel would compile them pretty early on. Regardless, some people who adopted async patterns early got into the habit of avoiding arrow functions entirely, so it wouldn't be crazy to me to hear someone say, "I used arrow functions before I learned async."

Otherwise, this is just restating the same arguments people already made above.

There's no practical reason why

  (() => {
  
  }());

would be useful but

  await (async () => {
  
  }());
wouldn't be. The scenario you're talking about where async code removes the need to have an anonymous function only makes sense if you were only using anonymous functions for callbacks. In practice, that's not the only (or even primary) use case for people who advocate inlining code in Javascript. They're specifically advising against the pattern where single-use functions are given names and removed from program flow.
Re:Stop writing lambda expressions in Python by joshuamorton on Friday September 28, 2018 @03:21PM (#18096250)
Correct, and I fundamentally disagree with that pattern. If it's more than a single expression, it's doing something complex enough to deserve a name or to be mocked in tests, etc.
Re:Stop writing lambda expressions in Python by dragonwriter on Friday September 28, 2018 @10:07AM (#18093452)
While I can see async/await replacing a lot of the most common use in JS, anonymous functions have a lot more uses than that (passing a single use function to generic algorithm, like an ordering function to a sorting routine, is one of the more common other uses, across languages.)