const evaluation

[benjamin...@gmail.com]

AFAIK, then the compiler does not perform const evaluation.

iex(9)> quote(do: 1+2*3)
{:+, [context: Elixir, imports: [{1, Kernel}, {2, Kernel}]],
 [1, {:*, [context: Elixir, imports: [{2, Kernel}]], [2, 3]}]}

iex(10)> quote(do: 1+2*3)

7

Are there any plans to implement this, if not what is the recommended approach to do this, when working on an AST.

[José Valim]

I believe we do it for certain functions in Elixir's stdlib and the Erlang compiler (which we invoke) does it too.

José Valim

https://dashbit.co/

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[Jean Klingler]

You can confirm it is done by the Erlang compiler using the beam_file lib for example (or `@compile :S`) and check the emitted byte code:

defmodule Foo do
  def foo, do: 1 + 2 * 3
end
|> BeamFile.byte_code!()

|> elem(5)

|> Enum.filter(&(elem(&1, 1) == :foo))

[
  {:function, :foo, 0, 11,
   [
     {:line, 1},
     {:label, 10},
     {:func_info, {:atom, Foo}, {:atom, :foo}, 0},
     {:label, 11},
     {:move, {:integer, 7}, {:x, 0}},
     :return
   ]}
]

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[benjamin...@gmail.com]

Yeah, I should have been clearer, I'm looking for const evaluation of expressions e.g 

iex> Code.string_to_quoted!("1+2*3")

7

[José Valim]

That's what the compiler does, as long as the code is compiled. It is not the job of a parser to do this.

José Valim

https://dashbit.co/

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[benjamin...@gmail.com]

Yeah, I’m looking for a compile snippet function as I’m only working with expression and not complete modules.