Iex -S mix: alias r() to recompile()

[zeroexcuses]

Inside an “iex -S mix” session, is it possible to alias “r()” to “recompile()” ?

[Exadra37]

@zeroexcuses

is it possible to alias “r()” to “recompile()” ?

If in iex you do h alias you will see that you can only alias a module, and you want to do it for a function.

As a side note they are two distinct functions as you can see by doing in iex h r and h recompile.

[zeroexcuses]

Interesting, I did not even realize, until now, that r/1 existed. How difficult is it to define a new r/0 ? Can this be achieved without recompiling mix, or is there no other way to do this?

[Exadra37]

@zeroexcuses

How difficult is it to define a new r/0 ? Can this be achieved without recompiling mix, or is there no other way to do this?

You will want to try this:

Can I extend iex helpers?

So Code.load_file didn’t work, but I found a solution: create a helper module (cd ~ && vim my_helpers.ex) compile the helper module (elixirc my_helpers.ex) add an import statement to .iex.exs (import MyHelpers) test in iex What happens is that iex auto-loads the compiled beam file - then you can auto-import the helper module in .iex.exs. You can tweak the beam-path by hacking the iex shell script (at /usr/local/bin/iex). @gregvaughn thanks for your suggestions!

While we are at it, you may want to take a look to:

https://itnext.io/a-collection-of-tips-for-elixirs-interactive-shell-iex-bff5e177405b

[hauleth]

In your $HOME/.iex.exs write:

defmodule Hauleth.IExHelpers do
  defdelegate r(), to: IEx.Helpers, as: :recompile
  defdelegate r!(), to: IEx.Helpers, as: :recompile!
end

import Hauleth.IExHelpers

[Exadra37]

@hauleth

defmodule Hauleth.IExHelpers do
  defdelegate r(), to: IEx.Helpers, as: :recompile
  defdelegate r!(), to: IEx.Helpers, as: :recompile!
end

import Hauleth.IExHelpers

According to the post I linked this will not work, it will throw:

Can I extend iex helpers?

My .iex.exs is exactly as you suggested. When I run iex, I see this error message: ** (CompileError) .iex.exs:11: module MyHelpers is not loaded but was defined. This happens when you depend on a module in the same context it is defined. ... If the module is defined at the top-level and you are trying to use it at the top-level, such is not supported by Elixir

But if you compile it first and then import it in $HOME/.iex.exs it will work fine

I like your module simplicity.

[zeroexcuses]

@hauleth , @Exadra37 : Thanks for pointing out the right pieces.

For anyone else finding this via search, here is the full solution:

cat dev/iex/y.elixir 
defmodule Y.IExHelpers do
  defdelegate r(), to: IEx.Helpers, as: :recompile
end

cat .iex.exs 
IEx.configure colors: [ eval_result: [:cyan, :bright ]]
import Y.IExHelpers

iex -pa ~/dev/iex -S mix