On Thu, Jun 20, 2024 at 06:00:02PM GMT, René Nyffenegger wrote: > I have a file with the following content: ... > show_arguments( > divert(1)X`'divert(0)1st, > divert(1)Y`'divert(0)2nd)
> - - - - - - > > I expected the > divert(1)X`'divert(0) > and > divert(1)Y`'divert(0)2nd) > > to divert the X and Y so that it is emitted at the end. > > Can someone explain why this is not the case? Argument collection has priority over diversions. divert() only controls where the final output of top-level macro expansions will be collected, but during argument collection, you are not producing top-level output. Perhaps the manual could be improved with an example showing this pitfall, as you are not the first to question it. But this is not unique to GNU M4; other historical implementations also have this same behavior of prioritizing argument collection over macro expansion output (I just tested FreeBSD's m4 at https://instantworkstation.com/virtual-machine to confirm). -- Eric Blake, Principal Software Engineer Red Hat, Inc. Virtualization: qemu.org | libguestfs.org
