In working with the ExUnit code, there are at least two places where I think being able to introspect on module attributes would be useful.
One is here <https://github.com/elixir-lang/elixir/blob/master/lib/ex_unit/lib/ex_unit/case.ex#L227-L233>. In this code it would be useful to know if a module attribute has been set already. This code checks to see if it has a value. However, if a user set the value to `nil`, this code wouldn't be able to tell. Another situation it would be useful, is in this PR: https://github.com/elixir-lang/elixir/pull/9181. Specifically, this check <https://github.com/elixir-lang/elixir/blob/e24a18338ef908aba8bf83e315d6e3938dbefce7/lib/ex_unit/lib/ex_unit/case.ex#L427-L431>, where it would also be useful to know if the attribute is registered with accumulate or not. So, the proposal is an API something like this: defmodule X do Module.register_attribute(__MODULE__, :foo, accumulate: true) @bar true Module.attribute_registered?(__MODULE__, :foo) #=> true Module.attribute_registered?(__MODULE__, :foo, accumulate: true) #=> true Module.attribute_registered?(__MODULE__, :foo, persist: true) #=> false Module.attribute_registered?(__MODULE__, :bar) #=> true Module.attribute_registered?(__MODULE__, :bar, accumulate: true) #=> false Module.attribute_registered?(__MODULE__, :baz) #=> false end The third argument would be a subset match of the options. Thoughts? -- You received this message because you are subscribed to the Google Groups "elixir-lang-core" group. To unsubscribe from this group and stop receiving emails from it, send an email to elixir-lang-core+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/elixir-lang-core/39c87e02-8ed2-49ed-9754-d0e8f0bafd7e%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
