Collect all variables mentioned in some syntax, free or otherwise.

iex> all_vars(quote do: x) |> Enum.map(&elem(&1, 0)) [:x] iex> all_vars(quote do: fn x -> x + 1 end) |> Enum.map(&elem(&1, 0)) [:x] iex> all_vars(quote do: fn x -> x + y end) |> Enum.map(&elem(&1, 0)) [:x, :y]

Return all variables that are free in an expression.

iex> freevars(quote do: fn x -> {^x, ^y, } = {1, 2, 3} end) |> Enum.map(&elem(&1, 0)) [:y]