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Comment by zem | Hacker News Reader

i hate the output of elm-format, though :( it's very wasteful of vertical space.

Tangential question:

Why do Haskell and Elm format lists like this?

    type alias Circle =
        { x : Float
        , y : Float
        , radius : Float
        }

...and not like this:

    type alias Circle = {
      x : Float,
      y : Float,
      radius : Float
    }

...? The first makes me shudder with revulsion every time I see it --- that's not where commas go, dammit --- and there must be a reason, which I've never been able to figure out.

The Elm style guide mentions in passing that trailing commas require a diff that adds a field to modify two lines but one, but that applies to leading commas too if you add the field at the beginning of the list.

I get why this bothers a lot of people, but OTOH I get why some people like it. I think the reason for the former in the mind of the user is that the comma clearly signifies that you are adding another value after it, and you save valuable key strokes not having to add a comma to the end of the preceding line just to add another k:v on the line you're concerned about.

Putting he comma at the start of the line allows for deleting any line without having to edit another (unless it's the first in which case the missing brace is more obvious IMHO.

The trailing comma is more easily missed I'd say.

- It allows you to easily delete a line without needing to also modify the line before. - It also makes your diffs cleaner. With the latter, if you add a line, you'll also have to inspect the `radius: Float` line when doing a code review, even though it only added a comma.

this diff, right here, is what i'm complaining about. i decided to bite the bullet and start running elm-format since it was part of the 0.17->0.18 automigration tool, but it has yet to grow on me.

https://github.com/martindemello/crosspad.elm/commit/c67deb4...

And this is why we have yet to converge. We are people, we have opinions! And some of us lead teams and make decisions.

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