kevinlang
How to tell if file is being executed directly
Let’s say I have a file, foo.exs with the following contents:
defmodule Foo do
def bar do
"foobar"
end
end
IO.puts(Foo.bar())
What I would like to do is not run the IO.puts statement if the file is not being run directly via elixir. Is there any way to do this? I see there is __ENV__.file, but not sure how I can use that to accomplish it.
How it is done in some other languages, for example:
I also understand that using Mix and having a greater separation of concerns can solve this particular problem, but I’m curious if its possible to do without using Mix at all.
Cheers,
First Post!
Nicd
I would rather refactor my code so that the modules that work both in a project and when run directly would be moved into .ex files, and then the code to be run directly would be in a .exs and use those modules.
Let’s say you have a foo.ex:
defmodule Foo do
def bar(), do: IO.puts("Bar!")
end
and a test.exs just containing Foo.bar(). Now you can run elixir -pr "*.ex" test.exs and it will print Bar!.
Another option which I suggest looking into (without knowing what you are actually trying to do) are Mix tasks (I know you wanted to avoid Mix but look into it). That allows you to have tasks in your project that can be run on the command line and that can use the modules of your project. Then you can run them with mix your.task.
If you elaborate on your exact use case, then maybe we can suggest other methods.
Popular in Questions
Other popular topics
Latest on Elixir Forum
Sponsor Spotlight
Deploy Phoenix to your own VPS with PaaS ease: push-to-deploy, zero downtime, auto SSL, managed Postgres. 14-day free trial at potions.io
Categories:
Sub Categories:
Forums
Popular Tags
- #ecto
- #liveview
- #troubleshooting
- #learning-elixir
- #deployment
- #library
- #erlang
- #testing
- #genserver
- #mix
- #absinthe
- #remote-other
- #otp
- #plug
- #how-to-question
- #macros
- #postgres
- #channels
- #elixirconf
- #exunit
- #discussion
- #code-sync
- #javascript
- #podcasts
- #onsite
- #dialyzer
- #docker
- #authentication
- #umbrella
- #full-time-contract
- #podcasts-by-brainlid
- #ecto-query
- #elixir-ls
- #phoenix_html
- #iex
- #blog-post
- #graphql
- #genstage
- #ai
- #websockets
- #supervisor
- #advent-of-code
- #elixirconf-us
- #distillery
- #processes
- #forms
- #api
- #metaprogramming
- #security
- #performance
Our Sponsors
Build Elixir applications with speed and confidence.
Supporting innovation across the BEAM ecosystem.
We build reliable cloud platforms for business-critical systems.
Catch errors, track performance, monitor hosts and more.
Real-time error tracking, performance insights, and observability for devs.
Practical resources that improve the lives of professional developers.
Producing high quality Elixir screencasts since 2017.
Enabling companies to succeed by building software people love.
The team behind Membrane, Popcorn, LiveDebugger. Available for hire.
Courses that'll move you from confusion to "Aha, now I get it!"