Hi Fernando,
Thanks for the feedback!
You're right that the example you provided doesn't work. But maybe there's
some way to evaluate within the caller's context (`__CALLER`)?
I tried this:
defmacro import_with_interpolation(t) do
t_string = Macro.to_string(t)
{t_evaled, _} = Code.eval_string(t_string, Macro.Env.vars(__CALLER__),
__CALLER__)
quote do
import_file_if_available unquote(t_evaled)
end
end
Unfortunately, that doesn't work because `Macro.Env.vars` just returns the
variable names, but not their values.
My original macro works for me because I was calling it exactly like this:
import_file_if_available_with_interpolation ".iex.#{Mix.env}.exs"
And `Mix.env` *can* be evaluated in the current environment just fine.
Is there not some way to get both the variables and their current values
from the `__CALLER__` context and pass that to `Code.eval_string`?
On Tuesday, February 11, 2020 at 3:21:28 AM UTC-5, Fernando Tapia Rico
wrote:
>
> Hi Kenny,
>
> Unfortunately, I think that macro will not work in all the scenarios :(
> For example:
>
> iex_type = if condition?, do: "foo", else: "bar"
> import_with_interpolation ".iex.#{iex_type}.exs"
>
> For you use case, I think you could use a similar macro:
>
> defmacro import_iex_type_file do
> iex_type = if condition?, do: "foo", else: "bar"
> iex_type_file = ".iex.#{iex_type}.exs"
>
> quote do
> import_file_if_available unquote(iex_type_file)
> end
> end
>
> Hope that helps :)
>
>
> On Monday, February 10, 2020 at 9:05:59 PM UTC+1, Kenny Evitt wrote:
>>
>> I recently discovered the wonders of `.iex.exs` files!
>>
>> But my colleague pointed out that we might want some code, e.g. `import
>> X`, to run only in specific environments. In particular we wanted some
>> code, specifically an `import X`, to NOT run in `:prod`.
>>
>> I created a post on Elixir Forum about this:
>>
>> - Environment-specific `import` in (project) `.iex.exs` file? -
>> Questions / Help - Elixir Forum
>> <https://elixirforum.com/t/environment-specific-import-in-project-iex-exs-file/28920>
>>
>> I ended-up with a solution that uses a macro to wrap calls to
>> `import_if_available` so that an interpolated string could be used:
>>
>> ```elixir
>> defmacro import_with_interpolation(t) do
>> t_string = Macro.to_string(t)
>> {t_evaled, _} = Code.eval_string(t_string)
>>
>> quote do
>> import_file_if_available unquote(t_evaled)
>> end
>> end
>> ```
>>
>> It seems like it would be easy enough to just update the existing
>> `import_if_available`. Or maybe my macro could be added to `IEx.Helpers`
>> separately.
>>
>> Thoughts? (Problems with my macro code?)
>>
>
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