bug#41981: Reference Manual on Vtables: Missing Information on Permission "h"

[Sebastian Miele <sebastian.miele@gmail.com>]

dsmich@roadrunner.com writes:
> Is is documented in the docstring:
>
> scheme@(guile-user)> ,d make-struct-layout

In the reference manual, a description of make-struct-layout directly
precedes the '(define* (make-vtable ..) ..)' example that cannot be
understood without somehow grasping what is documented about "h" in the
docstring of make-struct-layout. However, the description of
make-struct-layout in the reference manual says: "FIELDS is as described
under ‘make-vtable’ (*note Vtables::)". But that description lacks the
information on "h".

It may be a matter of opinion. But my opinion stronly is that
descriptions about the behavior around permission "h" do should appear
in the reference manual in two places: The description of make-vtable
and the description of make-struct/no-tail.

After glancing at libguile/struct.c, "w", "h", and the depreciated "r"
seem in fact to be all possible permissions. I will prepare a patch after
I finish getting a good overview of Guile.