Install old Erlang and Elixir version with asdf

Long Le — Mon, 15 Nov 2021 03:34:44 +0000

Last weekend, I installed old Erlang and Elixir version on my Mac and faced some issues that took me some time to research and resolve. I think I should share my experience here to help you saving your time if you encounter the same issues as me.
Firstly, what is asdf and how to install multiple versions of Erlang and Elixir using asdf. I read some posts that are really helpful but this one seems to be the best: https://thinkingelixir.com/install-elixir-using-asdf/

In summary, you need to do the following steps:

Install asdf (using homebrew, zsh plugin...).
Add erlang plugin to asdf. Asdf uses plugins to manage libraries.
Install the desired erlang version. Asdf will checkout erlang code and build this library on your machine. Problems come from here, I will explain on the issues section below.
Add elixir plugin to asdf.
Install the desired elixir version.

Notice that each Elixir release has multiple versions compiled with different major versions of Erlang/OTP. To maximize compatibility between Elixir and the Erlang runtime, choose a 1-otp-XY version that matches the major version of the runtime you installed in the previous step. For example:
```
asdf install elixir 1.11.2-otp-23
```
Set global (used for your whole computer) and local (used for specific directory) version.

Issues

When building erlang on your machine, you may encounter errors showing that cannot run some make commands. These issues are caused by the newest autoconf library version, a dependency of asdf. To solve this, please remove autoconf and then install it manually as the instruction in this link https://github.com/asdf-vm/asdf-erlang/issues/195#issuecomment-815999279
Cannot compile project after downgrading Elixir and Erlang. With this issue, please do some cleanups and then recompile the project:
```
rm -rf _build
mix deps.clean --all
mix clean
mix deps.get
mix compile
```
ElixirLS does not working. In my case, the newest ElixirLS version is 0.8.1, is not compatible with the installed Elixir version 1.10.3. So what I did is downgrade the ElixirLS to version 0.7.0:

Good luck!

Elixir intellisense stop working

Long Le — Sat, 11 Sep 2021 00:41:07 +0000

Recently, VSCode intellisense feature for elixir has stopped working on my Mac. Code autocomplete, go to definition, function description... are all failed. My colleagues encounter the same problem.
After researching, I found the root cause is ElixirLS has crashed from launching.

I tried to disable ElixirLS, close the editor, open the editor again and enable ElixirLS but no luck. I also tried to reinstall ElixirLS but nothing changes.
So I went to ElixirLS Github homepage, move to Troubleshooting region and I found the solution:

Remove .elixir_ls folder in project folder:
```
rm -rf .elixir_ls/ 
```
Close VSCode.
Open project in VSCode again, wait for ElixirLS run.
And voila!

Updated 2021-11-14:

If the above method does not work, you can try the final solution below:

Get your elixir path
```
which elixir
```
Edit the launch.sh file of elixir-ls extension (the file path can be seen in the log above), add the export PATH="elixir/path/here" before exec elixir command.

This way has an inconvenience that is every time you update the extension, you need to modify the launch.sh file again.

DEV Community: Long Le

Install old Erlang and Elixir version with asdf

Issues

Elixir intellisense stop working

Updated 2021-11-14: