[digitalzombie]

Elixir is prettier than Erlang but it really mess up on certain things.

Erlang have pattern matching via function with same name and you can tell if it's a group of pattern matching with semicolon and period. But with Elixir you can't tell it's just def and end.

Erlang's:

-module(recursive).

-export([fac/1]).

fac(N) when N == 0 -> 1;

fac(N) when N > 0 -> N * fac(N-1).

You can tell fac(N) both are in a group of pattern matching cause ';' and '.'. The '.' denote the last pattern matching function.

Elixir:

defmodule Factorial do

    def of(0), do: 1

    def of(n), do: n * of(n-1)

end

You can't tell because there is no ';' and '.'. This is a trivial case but when your Elixir's module have a tons of function in it, this issue become relevant.

[jknoepfler]

I honestly don't understand how this messes anything up... the elixir syntax produces something semantically equivalent with a lot less garbage. Opinions may differ I guess, but I find your Elixir example much easier to read than your Erlang example (I program in Elixir, so that's not much of a datapoint).

[BoorishBears]

Most of the garbage is because those aren't the closest equivalents.

This is the closest Erlang equivalent:

   fac(0) -> 1;
   fac(N) -> N * fac(N-1).

[titraprutr]

It's not only that. I think the bigger issue is that because of it's Ruby-like syntax it encourages newcomers to think in Ruby rather than in Erlang. Rather than emphasising what's the core of Erlang it attracts people with it's syntax, which is the least important aspect of a language.

[slrz]

I think you make the Erlang definition look unnecessarily awful.

fac(0) -> 1;

fac(N) -> N * fac(N-1).

Or is there a particular advantage to write it using guards?

[digitalzombie]

It's an example from http://learnyousomeerlang.com

[jknoepfler]

having a semantically significant distinction between ; and . is unnecessarily awful. That kind of crap is one of the reasons Elixir has so much support.

[mnd]

What you said is equivalent to a Python programmer saying that adding semantical value to the “end” keyword in Ruby is unnecessarily awful because you can achieve the same by giving meaning to the indentation level. It’s an entirely subjective matter.

I would also like to point out that Erlang has also very good support and has seen adoption in some very critical systems as opposed to CRUD web applications which is the main domain of Elixir. Most of Ericsson’s products use Erlang to a certain degree, there are a lot of banking systems and aviation systems which make use of Erlang as well, quite a few Internet companies use it to great success, and many more.

And by the way, the semantic meaning of “;” and “.” is an awful lot similar to their use in the English language, you are blowing it out of proportions. This is a trivial thing which you learn after a 10 minutes introduction to Erlang. For me, personally, if one has a problem understanding the meaning of “;” and “.” or learning a new syntax for that matter, I can easily conclude that I probably should not give that person any decision power in designing systems.

[ryeguy]

How does that matter? Anyone who uses this defines them in groups one after another. You aren't looking at the punctuation at the end of the line, you're looking at the following line to see if it's the same function name.

[digitalzombie]

It matter because you're assuming they will group it. IIRC Erlang forces you to group it.

[ryeguy]

It's an incredibly safe assumption to make, though. This isn't enough of a problem in practice to amount to a negative for elixir or a pro for erlang.