Warn if variable is used as function call

[Aleksei Magusev]

Hey folks,

This is a followup on the https://github.com/elixir-lang/elixir/issues/3268 issue.

The impact on Elixir itself is the following:

https://github.com/elixir-lang/elixir/commit/1ef9c9999c1ccf3c70bbaeebb1dd75b4109c9dd6

Mostly warnings for self, group_leader and some other calls.

Ecto output with this patch:

Only 6 warnings: 2 for self call.

Phoenix output with this patch:

28 warnings: 9 for self call.

What does everyone think about this change?

[Ben Wilson]

Is it possible to detect when a zero arity function is shadowed by a local variable and just warn about that?

[Aleksei Magusev]

It's possible, however It'll be other type of warning.

E.g. self = self() will warn in this case, but not with the current patch.