Allow capturing function whose name ends in ?

[jgallagher]

If I have a local function defined as

def different?(foo) do
    ...

then trying to capture the function as "&different?/1" results in the following error:

invalid args for &, expected an expression in the format of &Mod.fun/arity, &local/arity or a capture containing at least one argument as &1, got: different?()

Changing the name and capture to just "different" (no ?) works fine.

[jgallagher]

Should note that &MODULE.different?/1 works fine (as long as the function isn't private).

[jeremy-w]

I just ran into this as well. Here is a small test case:

defmodule CaptureTest do
  def is_working?() do
    :works
  end

  def simple() do
    :simple
  end

  def test() do
    #fns = [&simple/0]
    fns = [&is_working?/0]
    Enum.map fns, fn val -> val.() end
  end
end

It will currently error during compilation. If you swap which of the fns definition lines is commented, you won't get an error.