lud

lud

Hi,

I guess I do not understand how ElixirLS works.

Test code:

defmodule MyApp do
  def hello do
    default(1)
  end

  @spec default(binary) :: binary
  def default(bin) when is_binary(bin) do
    "test #{bin}"
  end
end

Output:

Started ElixirLS v0.7.0
Elixir version: "1.12.1 (compiled with Erlang/OTP 24)"
Erlang version: "24"
ElixirLS compiled with Elixir 1.8.2 and erlang 21

Now I understand that there is a version mismatch but the vscode extension comes with precompiled beam files, so how could the version be the same?

Dialyzer (ran with dialyxir) succesfully reports the error, but ElixirLS is not showing the yellow vvvvvv. It should show that Function hello/0 has no local return.

What should I check now to make it work?

Showing Posts 1 to 10

NobbZ

NobbZ

What are your elixirLS.dialyzerEnabled settings?

lud

lud OP

Not defined. Same behaviour with explicit true.

lukaszsamson

lukaszsamson

ElixirLS Core Team
lud

lud OP

I don’t doubt ElixirLS works. It does not on my machine and I’m trying to figure out why :slight_smile:

luizdamim

luizdamim

Look in the Output pane in VS Code (remember to select Elixir LS in the dropdown) to see if there’s some explicit problem.

lud

lud OP

Hi,

Thank you for your reply. I posted part of the output in my first post. Besides the versions, there is nothing special in it.

michallepicki

michallepicki

I can see the issue with Erlang 24.0. Switching to Erlang 24.0.3 fixes it.

Sebb

Sebb

I can partially reproduce with OTP 22 and 24 (switched between these 3 times and always the same behaviour). 22 shows both warnings, 24 only one.

$ asdf global erlang 22.3.4.20 
$ asdf global elixir 1.11.4-otp-22

--> Function hello/0 has no local return.
--> The function call will not succeed. (MyApp.default(1))
$ asdf global erlang 24.0.3 
$ asdf global elixir 1.12.2-otp-24 

--> Function hello/0 has no local return.

also showing both:

erlang 23.3.4.1  
elixir 1.12.1-otp-23 

Which Elixir version?

EDIT:
I installed erlang 24.0. and can confirm, that I also do not get any warnings displayed.
Also the output of ElixirLS differs.

Output with 24.0.3:

Started ElixirLS v0.7.0
Elixir version: "1.12.2 (compiled with Erlang/OTP 24)"
Erlang version: "24" # 24.0.3
ElixirLS compiled with Elixir 1.8.2 and erlang 21
MIX_ENV: test
MIX_TARGET: 
[Info  - 1:54:55 PM] Compile took 732 milliseconds
[Info  - 1:54:55 PM] [ElixirLS Dialyzer] Checking for stale beam files
[Info  - 1:54:55 PM] [ElixirLS WorkspaceSymbols] Indexing...
[Info  - 1:54:55 PM] [ElixirLS Dialyzer] Found 32 changed files in 26 milliseconds
[Info  - 1:54:55 PM] [ElixirLS Dialyzer] Analyzing 0 modules: []
[Info  - 1:54:55 PM] [ElixirLS Dialyzer] Analysis finished in 28 milliseconds
[Info  - 1:54:55 PM] [ElixirLS WorkspaceSymbols] Module discovery complete
[Info  - 1:54:55 PM] Dialyzer analysis is up to date
[Info  - 1:54:55 PM] [ElixirLS WorkspaceSymbols] 181 modules added to index
[Info  - 1:54:55 PM] [ElixirLS WorkspaceSymbols] 22 callbacks added to index
[Info  - 1:54:56 PM] [ElixirLS Dialyzer] Writing manifest...
[Info  - 1:54:56 PM] [ElixirLS WorkspaceSymbols] 280 types added to index
[Info  - 1:54:58 PM] [ElixirLS Dialyzer] Done writing manifest in 3144 milliseconds.
[Info  - 1:55:02 PM] [ElixirLS WorkspaceSymbols] 3971 functions added to index

Output with 24.0:

Started ElixirLS v0.7.0
Elixir version: "1.12.2 (compiled with Erlang/OTP 24)"
Erlang version: "24" # 24.0
ElixirLS compiled with Elixir 1.8.2 and erlang 21
MIX_ENV: test
MIX_TARGET: 
[Info  - 1:56:52 PM] Compile took 605 milliseconds
[Info  - 1:56:52 PM] [ElixirLS WorkspaceSymbols] Indexing...
[Info  - 1:56:52 PM] [ElixirLS Dialyzer] Checking for stale beam files
[Info  - 1:56:52 PM] [ElixirLS Dialyzer] Found 32 changed files in 21 milliseconds
[Info  - 1:56:52 PM] [ElixirLS WorkspaceSymbols] Module discovery complete
[Info  - 1:56:52 PM] [ElixirLS WorkspaceSymbols] 26 callbacks added to index
[Info  - 1:56:52 PM] [ElixirLS WorkspaceSymbols] 185 modules added to index
[Info  - 1:56:52 PM] [ElixirLS WorkspaceSymbols] 285 types added to index
[Info  - 1:56:55 PM] [ElixirLS WorkspaceSymbols] 3990 functions added to index
michallepicki

michallepicki

I think Elixir version doesn’t make a difference, to reproduce just use erlang 24.0 (without any patches) or erlang 24.0.2 and there will be no warnings shown. Dialyzer returns

{:warn_return_no_exit, {'lib/my_app.ex', 0}, {:no_return, [:only_normal, :hello, 0]}}

so this is probably related to Fix lost line numbers in Dialyzer warnings for Elixir code by michallepicki · Pull Request #4890 · erlang/otp · GitHub. With 24.0.3 I also see only one warning.

Sebb

Sebb

can confirm that there are no warnings with erlang 24.0 and 24.0.2. But still there is a warning missing for 24.0.3

Where Next? Top

Trending in Questions Top

katta
I having some trouble figuring out if I have set myself too strict of standards for my production server. Currently I can handle 75% of r...
New
nseaSeb
Hello, I know there is an approach for handling lists that allows for optimized traversal, but I can’t recall the specific method (somet...
New
brecabral
Documentation While reading the Scoped Routes section, I noticed that the documentation currently refers to a problem without explainin...
New
kpanic
Hi everyone, I am toying with the idea of building a “match maker” for giving personal help to people that wants to start coding. I sta...
New
velrest
So my question is quite simple and i have found no conclusive answer on forum, google or AI. Should we use :erlang.float for Integer to ...
New
asweet-confluent
I recently noticed that Elixir’s Logger defaults its primary log level to :debug when no :logger, :level application configuration is pre...
New
apz
I’m new to elixir and just tried to install the elixirLS extension for VScode(ium) and it is throwing some errors that I would like help ...
New

Other Trending Topics Top

GenericJam
Edit: 2026 May 15 - This post is archived. Mob is alive!! Main docs: mob v0.7.11 — Documentation A bit of explanation for the slightly c...
New
JesseHerrick
Hey, I’m Jesse and I’m the main contributor behind Dexter, a full-featured, lightning-fast Elixir LSP optimized for large codebases. It s...
New
mudasobwa
I am happy to introduce the very α version of the new programming language compiled to BEAM. Welcome Cure. It has literally three kille...
New
garrison
Hobbes is a low-level distributed database for the Elixir programming language. Hobbes provides a simple, safe, and scalable storage lay...
New
mhanberg
Hi everyone! The first release candidate for the Expert language server project is now available! We’ve published a press release detai...
New
budgie
A little off-topic, but I feel like people here have a good head on their shoulders. I used to be quite good at making software. Was luc...
New

We're in Beta

About us Mission Statement

Options

Thread Display Mode




Thread Preview

Skip Thread Previews