Require as function name should not appear as blue

[nicobao]

Special reserved words can actually be used as function name as well. For example with require. The first usage, require Foo shows that "require" is highlighted in blue. That's good. The second usage, require(fields, :title, &validate_title/1), is also displayed in blue. It should not. It is a normal function and should be displayed in white.

The same behaviour can be seen with function named import.

I'm happy to start working on a patch, but I'd need initial guidance.

[axelson]

A patch for require would be accepted, but unfortunately I can't give much guidance on how you'd accomplish this (or how much work it would be). It looks like require is identified as a keyword at https://github.com/elixir-editors/emacs-elixir/blob/231291ecadc479295d83fee619049030940bfbe5/elixir-mode.el#L123

[nicobao]

Hi @axelson! Thanks for your reply. I read on the Slack that people suggested having Semantic colouring and you talked about that PR: https://github.com/microsoft/language-server-protocol/issues/18 Indeed, I was too ambitious in suggesting I could help, I wish I could but I have no time for it right now :/. I don't think it is a very important problem anyway. I can live with it. Honestly, I am more bothered by the issue related to smartparens. If it is the same for all users, the smartparens issue should probably have higher priority.

[jsmestad]

@nicobao this should be a pretty easy fix because require cannot be followed by parens when it's a function versus a Kernel method (when it should show up as blue). Right?

If you can confirm that is right, I can put a patch together.

[victorolinasc]

@jsmestad unfortunately it is not so simple...

iex(1)> defmodule Test do
...(1)>   require(Logger)
...(1)> end
{:module, Test,
 <<70, 79, 82, 49, 0, 0, 3, 80, 66, 69, 65, 77, 65, 116, 85, 56, 0, 0, 0, 118,
   0, 0, 0, 12, 11, 69, 108, 105, 120, 105, 114, 46, 84, 101, 115, 116, 8, 95,
   95, 105, 110, 102, 111, 95, 95, 7, 99, ...>>, Logger}
iex(2)> 

Kernel.require is certainly a macro as any other in terms of syntax. What makes it even harder is that it can be scoped inside a function too:

iex(1)> defmodule Test do
...(1)>   def some_func do
...(1)>     require(Logger)
...(1)>   end
...(1)> end
{:module, Test,
 <<70, 79, 82, 49, 0, 0, 4, 36, 66, 69, 65, 77, 65, 116, 85, 56, 0, 0, 0, 142,
   0, 0, 0, 14, 11, 69, 108, 105, 120, 105, 114, 46, 84, 101, 115, 116, 8, 95,
   95, 105, 110, 102, 111, 95, 95, 7, 99, ...>>, {:some_func, 0}}
iex(2)>

Perhaps we should have a face for function calls with parentheses and another for function calls without parentheses. For example:

defmodule MyRouter do
  plug :my_plug # no parentheses call should
  plug(MyPlug, options: "an option")
end

Then at least this could be configurable. This is how the GitHub syntax highlight works. Not sure how it works in other editors though...