011 std for nested

// Test 320_011: ~for with nested continuations (chained events)
// Tests that ~for correctly handles | each |> event1() | result |> event2() patterns
//
// SEMANTICS:
// - | each item |> step1() invokes step1 for each element
// - | result r |> step2() handles step1's result and chains to step2
// - | done |> runs ONCE after iteration completes
//
// This tests the continuation_codegen helper generating proper switch statements.

const std = @import("std");

~import "$std/control"

// Event 1: double a number
~event double { x: i32 }
| result { y: i32 }

~proc double {
    return .{ .result = .{ .y = x * 2 } };
}

// Event 2: print a number
~event print_num { y: i32 }

~proc print_num {
    std.debug.print("{}\n", .{y});
}

// Event to finalize
~event finalize {}

~proc finalize {
    std.debug.print("done\n", .{});
}

// Test data
const items = [_]i32{ 1, 2, 3 };

// The for loop with chained events
// Each item: double it, then print the result
~for(&items)
| each item |> double(x: item)
    | result r |> print_num(y: r.y)
| done |> finalize()