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Sure, you'd code like

    SCOPE(Resource *ptr = acquire_resource(),
          release_resource(ptr))
    {
        // do stuff with resource ptr.
    }
Actually, to allow variable declarations in the init_stmt like above, you'll need to use two nested for-loops:

    #define SCOPE_(name, begin_stmt, end_stmt) for (int name = 0; !name; assert(name && "should never break from a SCOPE")) for (begin_stmt; !name; name++, (end_stmt))
It is natural to add another layer of specific usage macro like this:

    #define UI_NODE(ctx) SCOPE(push_ui_node(ctx), pop_ui_node(ctx))

    UI_NODE(ctx)
    {
        ui_color(ctx, UI_COLOR_RED);

        const char *items[3] = { "a", "b", "c" };
        for (int i = 0; i < 3; i++)
        {
            UI_NODE(ctx)
                ui_text(ctx, items[i]);
        }
    }
Naturally, if you're already on C++, better code these macros in terms of RAII instead of abusing for-loops. That will add a little robustness.


I'm on C89, but this is a very useful trick. Thanks!




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