023 comptime program return

// TEST: Comptime events can return modified Program
//
// A [comptime] event that declares `program: *const Program` in its OUTPUT
// should have that Program used as the new AST going forward.
//
// This enables holistic AST transformations without needing [transform].
// Transforms are for surgical replacement of specific invocations.
// Comptime + Program return is for cross-cutting AST modifications.

const std = @import("std");
const ast = @import("ast");
const ast_functional = @import("ast_functional");

// Comptime event that RETURNS a modified Program
~[comptime] event augment_program {
    program: *const ast.Program,
    allocator: std.mem.Allocator
}
| done { program: *const ast.Program }

~[comptime] proc augment_program {
    // Use ast_functional to add a new item to the program
    // For now, just return the program unchanged
    std.debug.print("augment_program: received {} items\n", .{program.items.len});

    // TODO: Actually modify the program using ast_functional
    // const new_program = ast_functional.addItem(allocator, program, new_item);
    // return .{ .done = .{ .program = new_program } };

    return .{ .done = .{ .program = program } };
}

// Invoke the augmentation
~augment_program()
| done _ |> _

// A simple runtime event to verify compilation works
~event hello {}
| greeted {}

~proc hello {
    std.debug.print("Hello from augmented program!\n", .{});
    return .{ .greeted = .{} };
}

~hello()
| greeted |> _