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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Help requested with P99-based macro to create Wayland listeners
Date: Tue, 09 Apr 2024 09:22:46 -0700
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Blue-Maned_Hawk <bluemanedhawk@invalid.invalid> writes:

> This macro doesn't work and i don't know why.  I've tried multiple
> different things to try to delay the expansion of _0MAKE_LISTENER and none
> of them have worked.  I don't know if there's a more idiomatic way to do
> this.  I've tried looking at the output from putting it through ?cpp?  and
> that didn't work because it errored out before i could see what it
> expanded to.
>
> #define MAKE_LISTENER(object_type, ...) static const struct\
> object_type##_listener object_type##_listener = { P99_SEQ(\
> _0MAKE_LISTENER, P99_SEQ((object_type), __VA_ARGS__)) }
> #define _0MAKE_LISTENER(x) _1MAKE_LISTENER (x, _2MAKE_LISTENER
> #define _1MAKE_LISTENER _3MAKE_LISTENER
> #define _2MAKE_LISTENER(y) y)
> #define _3MAKE_LISTENER _4MAKE_LISTENER
> #define _4MAKE_LISTENER(object_type, event_name) .event_name =\
> callback_##object_type##_##event_name

What is it that you want to accomplish?