[pmontra]

The idiomatic way to do that is to match errors in the else branch of the with statement.

I've been using Elixir and Phoenix for a customer for a couple of years. It's ok to great, especially when spawning jobs, with some stains.

I'm not a great fan of the with syntax. I wish they implemented it as a native statement of the language instead of as a macro. In that way they probably could let us write the same code inside and outside a with, instead of having to transform = into <- and add a comma.

But the worst offenders are GenServers. They should really have the syntax of OO classes instead of the incomprehensible handle* functions. After all that's what they are, objects with their own CPU. (Remember Armstrong about Erlang being the only true OO language?)

By the way, that would make it easier to code, to understand and to migrate people from imperative languages.

[sb8244]

I think one of the big points about being a true OO language is that the only way to talk to a process is via message passing. To me, the handle concept makes sense when you consider that it's handling a message in its mailbox.

[pmontra]

Yes, I see that but it's an unnecessary complication. All I want to do client side is calling Module.func() and GenServer side I wish I could only def func() instead of all those incantations.

Furthermore GenServers mix client side and server side code in the same module. It's very confusing even after years. It's one of the most unpleasant coding experience of the decade for me.

On the other side I'd steal Elixir's pattern matching implementation and add it to every language. It's everywhere in Elixir and IMHO it's its strongest point.

[mercer]

I think Dave Thomas has a bunch of comments on the elixir forums, and perhaps blog articles and videos too that express a similar problem with GenServers. might be interesting to look those up.

IIRC, one approach he encourages is to at the very least keep most of your logic in a separate module rather than have just a GenServer module that contains a bunch of regular functions and a bunch of handle_<x> functions (which is kind of idiomatic, or at least what I've always been taught).

That said, it's been a while since I followed this discussion so I'd be happy to be corrected.

EDIT: calling a 'public' function in a GenServer and having a handle_<x> function actually deal with it does seem to have an explicitness about it that I think I like. Learning about processes and how they work, I imagine I might've gotten confused if a seemingly normal functional call somehow magically handed things off to a different process.

[verttii]

Yeah you may be on to something here. Looking at GenServer callbacks as some sort of pure independent functions would not make a lot of sense, they're tightly coupled to processes/GenServer anyway.