Generate functions at compile-time

Question

Is there any way to generate functions at compile-time in Ada? I want to generate an opcode table that stores function pointers. My current solution is to store objects containing a procedure that can be executed, but I'd rather not allocate if possible.

Maybe you should show us a short, but representative example of what you are doing at the moment. — Jacob Sparre Andersen, Jul 27 '18 at 19:19
Are you sure you mean to *generate* functions at compile-time? — Jacob Sparre Andersen, Jul 27 '18 at 19:21
I’m away from my computer right now, but I may post something when I get back. Essentially I have a bunch of functions that are generally very similar that I don’t want to maintain separately (for example, a bunch of LD instructions). In Rust, I would use a macro here. — Arcterus, Jul 27 '18 at 23:22

score 3 · Accepted Answer · answered Jul 27 '18 at 19:18

3

No.

But there's nothing wrong with having a domain-specific language (DSL) from which you generate Ada. That happens regularly.

answered Jul 27 '18 at 19:18

Jacob Sparre Andersen

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I had a feeling that was the case. I’ll guess I’ll just write a script to generate them (or use some preprocessor). – Arcterus Jul 27 '18 at 23:29

score 3 · Answer 2 · answered Jul 28 '18 at 13:23

You can use a generic procedure to have a generic body and just supply whatever unique parameters you need to it

with Ada.Text_IO; use Ada.Text_IO;

procedure Hello is
    generic
        -- some sort of parameters
        Value : Integer;
    procedure Do_Op;

    procedure Do_Op is
    begin
        Put_Line(Integer'Image(Value));
    end Do_Op;

    procedure Op1 is new Do_Op(1);
    procedure Op2 is new Do_Op(2);
    procedure Op3 is new Do_Op(3);


begin
  Put_Line("Hello, world!");
  Op1;
  Op2;
  Op3;
end Hello;

Generate functions at compile-time

2 Answers2