Try mise install elixir@1.18-otp-27
stefanluptak
woylie
Roughly:
{
description = "Dev environment for Elixir/Nodejs";
inputs = {
nixpkgs = { url = "github:NixOS/nixpkgs/nixos-unstable"; };
flake-utils = { url = "github:numtide/flake-utils"; };
};
outputs = { self, nixpkgs, flake-utils }:
flake-utils.lib.eachDefaultSystem (system:
let
inherit (pkgs.lib) optional optionals;
pkgs = import nixpkgs { inherit system; };
myPkgs = {
erlang = {
defaultPackage = pkgs.erlang_27;
useOverride = false;
overrideVersion = "27.0.0";
overrideSha256 = "cuFeHwyAyS8R7rXcJJxzE7LTZGgDr4x3qMZx63PIowm=";
};
elixir = {
defaultPackage = beamPkg.elixir_1_17;
useOverride = true;
overrideVersion = "1.18.0-rc.0";
overrideSha256 = "OvUL/48gQ4a5TPy1l76+HBF2PoEDAHT9+MC8XNdrSmI=";
};
};
erlang =
if myPkgs.erlang.useOverride
then
pkgs.erlangR25.override
{
version = myPkgs.erlang.overrideVersion;
sha256 = myPkgs.erlang.overriderSha256;
}
else myPkgs.erlang.defaultPackage;
beamPkg = pkgs.beam.packagesWith erlang;
elixir =
if myPkgs.elixir.useOverride
then
beamPkg.elixir.override
{
version = myPkgs.elixir.overrideVersion;
sha256 = myPkgs.elixir.overrideSha256;
}
else myPkgs.elixir.defaultPackage;
in
with pkgs;
{
devShell = pkgs.mkShell {
buildInputs = [
elixir
glibcLocales
nodejs_22
] ++ optional stdenv.isLinux inotify-tools
++ optional stdenv.isDarwin terminal-notifier
++ optionals stdenv.isDarwin (with darwin.apple_sdk.frameworks; [
CoreFoundation
CoreServices
]);
};
});
}
4
billylanchantin
Hey since we’re talking about this, I’m having a similar problem to @martosaur in this doctest:
I tried this:
iex> Process.get(:not_a_key, a < b)
But I still got warning: comparison with structs found:. Anyone have any thoughts?
I can always change the part that warns to prose if there isn’t a workaround.
0
lud
I have not been following the whole thread but when you call compare?(a < b, Date), is compare?/2 a macro?
If not then it’s first argument is a < b which is comparing structs, whatever you do with the result afterwards.
Same with Process.get(:not_a_key, a < b) but as José said you want the operator out of the call, like this: Process.get(:not_a_key, a) < b.
1
billylanchantin
is
compare?/2a macro?
Yep! Its purpose is so that you can write:
compare?(a < b, Date)
And it gets translated to the correct:
Date.compare(a, b) == :lt
You can read more here: CompareChain - Semantic, chained comparisons for Elixir
but as José said you want the operator out of the call, like this:
Process.get(:not_a_key, a) < b.
Thanks, I was skimming and missed this point. But it didn’t work either 
3
harrisi
I think you need to do the Process.get trick for both values: Process.get(:not_a_key, a) < Process.get(:not_a_key, b).
1
billylanchantin
zachdaniel
Creator of Ash
I think over time the introduction of a smarter compiler could warrant the introduction of tools to work with it that make their purpose clear. For example:
Kernel.dynamic_value/1
# takes anything, returns it as a dynamic
dynamic_value(1) + "test"
Kernel.unreachable!/1
case something do
:foo -> 10
:bar ->
# somehow tells the type checker not to warn on this clause?
unreachable!("It should not be possible for `something` to be `:bar` at this point.")
end
2
josevalim
Creator of Elixir
In this case, you should just remove the a < b from the doctest by removing iex> and have it written as non-executable code. I think using Process.get in the doctest would detract from its main purpose, which is documentation.
That’s the plan in the long term, but something like dynamic_value can also be used to hide actual bugs, so we want to tread carefully.
4
sodapopcan
Was gonna say, this is was giving me any type vibes only right in code. Feels like it should be a special form that somehow only works in ExUnit. Or perhaps be called Kernel.return_dynamic_value_but_only_use_this_function_in_tests_ok? 
2