when at callsite

// Test 915: VERIFY when clause is at CALL SITE, not inside tap
//
// The ONLY way to verify this is to CHECK THE GENERATED CODE
// This test expects a specific pattern in output_emitted.zig

const std = @import("std");

~event produce { value: u32 }
| done { result: u32 }

~proc produce {
    const result = value * 2;
    std.debug.print("Produced: {}\n", .{result});
    return .{ .done = .{ .result = result } };
}

~event log { result: u32 }
| done {}

~proc log {
    std.debug.print("Logging: {}\n", .{result});
    return .{ .done = .{} };
}

// Tap with when clause
~produce -> *
| done d when d.result > 50 |> log(result: d.result)
    | done |> _

~produce(value: 10)
| done |> _

~produce(value: 30)
| done |> _