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Comment by jswny | Hacker News Reader

Can you explain what you mean about module naming? I’ve done a good amount of Elixir, and I’m puzzled because I don’t know what you are referring to at all.

Most libraries and frameworks I’ve used enforce things on your modules via behaviors which have nothing to do with naming. Perhaps you are talking about naming functions for behaviors? Because I think it’s the same in most languages that “overridden” or “implementations” of functions for modules/classes that use some kind of interface must be named the same as the interface definition.

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> Perhaps you are talking about naming functions for behaviors? Because I think it’s the same in most languages that “overridden” or “implementations” of functions for modules/classes that use some kind of interface must be named the same as the interface definition.

Yes. In typescript, you can have abstract classes or interfaces to implement which gives you more information (intellisense, visible errors, type information) and make the contract more explicit. I was trying out phoenix and I didn't get any hints about the methods to implement in the module. I was relying on documentation for that. If there was a way to say use @some_spec and get information about it in the editor. It would have helped out.

The compiler will warn you about things like unimplemented functions that are required by behaviors, and there are plugins for various editors to display errors/warnings inline.

There's also Dialyzer (and various IDE integrations) for some level of static type-checking.

there are language features directly for this. no need to rely on compiler hints or dialyzer.

elixir people really should learn erlang.

if you ever saw a coffeescript person struggling to do things that are straightforward in js, because they didn't bother to learn js? that's what you're doing now

This is the main reason why I learn programming languages to broaden my knowledge, but when it comes to production code, only platform languages matter.

Well no, it's just that Elixir is built on Erlang, so everything Erlang has is in Elixir

If you learn the base language, you get more powerful in the descendant language as well

If one only uses the base language, no need to worry about the fate of the descendant language or how it exposes base language features.

This means you're arguing that one should never learn anything except machine code because machine code is what it all turns into at the end of the day.

Only you DO use languages that end up as machine code, and the idea of understanding machine code to better utilize something like C isn't outlandish.

Nope, use C/C++/Perl/awk with UNIX, Java with the JVM, C++/Swift/Objective-C with iOS/macOS, Java/Kotlin/C++ with Android, VB.NET/C#/F#/C++ with Windows, JavaScript/WebAssembly with the Browser,.... and naturally Erlang/C with BEAM.

No need for extra build tools, FFI with the platform language, additional debugging tools, the urge to create wrapper libraries that feel more idiomatic into the guest language, waiting for the guest language to come up with ways to expose new platform capabilities,...

Guest languages are good for experimenting new ideas that eventually get adopted by the platform and then the world moves on, and they turn into the next CoffeeScript.

> In typescript, you can have abstract classes or interfaces to implement

In erlang these are called "behaviours"

> I was relying on documentation for that

Consider reading the Erlang documentation. The Elixir people really don't understand Erlang very well, and are trying to manufacture Ruby on top of a language that already gives them solutions to their problems that they just can't see.

> If there was a way to say use @some_spec and get information about it in the editor. It would have helped out.

Basically every IDE that speaks Erlang knows behaviors. They're as fundamental to the language as header files are to C/C++.

Elixir tried to "do away with them" because Elixir thinks they're "confusing" but they're actually really important tools.

Elixir does not try to do away with them. They are covered in the official guide: https://elixir-lang.org/getting-started/typespecs-and-behavi...

As soon as I add @behaviour to a module, I get IDE autocomplete and compiler warnings if a function has not been implemented.

I do agree that I have not seen a lot of behaviour use in the wild, even in cases where it's clear that they would be beneficial. Elixir developers seem to have some blindspots.

> As soon as I add @behaviour to a module, I get IDE autocomplete and compiler warnings if a function has not been implemented.

It is exactly what I was looking for. Thanks for mentioning it.

Elixir hasn’t done away with behaviours. They exist in the language and are used to implement features in the standard library itself and many libraries in the ecosystem.

You don’t have to go to Erlang documentation to learn about them since they are documented in Elixir as well [1] [2].

[1] https://elixir-lang.org/getting-started/typespecs-and-behavi... [2] https://elixir-lang.org/getting-started/typespecs-and-behavi...

> Elixir tried to "do away with them" because Elixir thinks they're "confusing" but they're actually really important tools.

That's completely inaccurate. They are an important part of Elixir and they are fully documented.

Elixir even has annotations that allow you to say "this function maps to a behaviour's callback". For example:

    @behaviour GenServer

    @impl true
    def handle_info(msg, state)

Those are important because, with optional callbacks, you can make a typo on the function name or on the number of arguments and you won't get any warning, in both Erlang and Elixir. "@impl true" allows you to close this gap.

So we do support behaviours and we have added more static guarantees compared to what you would find in Erlang.

> The Elixir people really don't understand Erlang very well

It is a bit depressing it has come to this but my long list of contributions to Erlang/OTP through pull requests, discussions, EEPs, etc say otherwise.

I wouldn't feed the troll. The many people who know and appreciate your language realise how much of an improvement Elixir represents over Erlang.

Including Joe Armstrong himself... https://joearms.github.io/published/2013-05-31-a-week-with-e... ^_^

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