Fl4m3Ph03n1x

Fl4m3Ph03n1x

Cannot compile attribute

I am trying to compile a simple module where I get a module from the config and save it on an attribute.

defmodule Test do
  @metrics                  Application.get_env(:my_app, :metrics_module)
  @default_deps %{
    count_error:  &@metrics.inc/1
  }
end

However I cannot even compile the code for I have the following error:

== Compilation error in file lib/worker/worker.ex ==
** (ArgumentError) cannot inject attribute @default_deps into function/macro because cannot escape #Function<0.55850841 in file:lib/worker/worker.ex>. The supported values are: lists, tuples, maps, atoms, numbers, bitstrings, PIDs and remote functions in the format &Mod.fun/arity
    (elixir) lib/kernel.ex:2879: Kernel.do_at/5
    (elixir) expanding macro: Kernel.@/1
    lib/worker/worker.ex:47: Cooper.Worker.find/1
    (elixir) lib/kernel/parallel_compiler.ex:208: anonymous fn/4 in Kernel.ParallelCompiler.spawn_workers/6

Why can’t this compile given that my dev.exs does have that parameter defined?

Marked As Solved

NobbZ

NobbZ

You simply can not put anonymous function into a module attribute. This is a limitation of the language.

Try saving it as a MF-tuple.

You’ll need extra work to call it then though.

Something like this:

@def_deps %{ count_error: {@metrics, :inc} }

def dosomething() do
  {m, f} = @def_deps.count_error
  apply(m, f, [:dosomething])
end

Where Next?

Popular in Questions Top

belgoros
I’m not a pro in using Regex and can’t figure out why the following behaviour happens, especially if we take into account the difference ...
New
lastday4you
I wanted to check elixir version in phoenix because i found that my elixir is 1.5 but when i use Enum.chunk_by it said the function is un...
New
joaquinalcerro
Hi there, I am working with Ecto-Postgresql and I need to call all of the records from a specific table but the table has 40,000 record...
New
openscript
Hello! Sorry for this astonishing simple question, but I’m really stuck. I try to set up the intellij-elixir plugin, but I don’t know ho...
New
Werner
Hi, I’m using Ubuntu 18.04 and after updating to OTP-24.0 yesterday i have this warning when I run “mix local.hex”: 14:57:30.512 [warn] ...
New
Kagamiiiii
Student &amp; New to elixir. Nice language. I want to convert a english character, e.g. “a”, which is stored in a variable, to it’s asci...
New
myronmarston
The Elixir Typespec docs show the following syntax for keyword lists in typespecs: # ... | [key: type] # keyword lis...
New
fayddelight
I tried installing elixir 1.11.2 erlang 23.3.4 via asdf in my zsh shell. Enabled the versions locally and globally. When I list them ...
New
chewm
Hi guys, nice to meet you to the whole forum, I’m new here, I’m trying to configure visual studio code for elixir, right now the intellis...
New
joeerl
Hello again - after a longish gap I’ve decided I really must dig into Elixir and see what’s been happening here - so I have a few questio...
New

Other popular topics Top

vrod
I am using the Starship cross-shell prompt – it seems pretty nice, but I get some errors: [WARN] - (starship::utils): Executing command ...
New
JakeBecker
TL;DR: I’ve just released an implementation of Microsoft’s IDE-independent Language Server Protocol for Elixir. It adds language support ...
1140 51847 244
New
jononomo
I am trying to figure out how Mix knows whether the environment is test, dev, or prod -- where is this set? Thanks.
New
malloryerik
Hi, this is for people who, like me, have had some friction using .html.heex templates in VSCode. The solution seems to be, in a hyphena...
New
sacepums
Hey guys. I'm new to elixir and im really stocked about it. But I ran into a bit of problem - I need to convert a date sting, for examp...
New
nsuchy
Hi. I’ve noticed that Windows Powershell has it’s own IEX command and you cannot access Elixir’s IEX due to the conflict. This isn’t a cr...
New
chrismccord
As promised, the first release candidate of Phoenix 1.3.0 is out! This release focuses on code generators with improved project structure...
New
danschultzer
None of the current solutions worked well for me, so I went ahead and built a user management system from scratch. This project took far...
548 27727 240
New
fireproofsocks
Forgive me if this is obvious, but how does one delete a database record WITHOUT selecting it first? https://hexdocs.pm/ecto/Ecto.Repo.h...
New
baxterw3b
Hi guys, i’m new in the Elixir world, and i have to say, that i love it! i’m having some problem to understand anonymous functions with ...
New

We're in Beta

About us Mission Statement