* doc/ref/api-memory.texi (Garbage Collection Functions):
* doc/ref/libguile-concepts.texi (Garbage Collection): Attempt to be
clear that scanning is a thing that happens in the mark phase. Fixes
#20907 I think.
* doc/ref/api-memory.texi (Memory Blocks): Recommend against
scm_gc_free. Refer to foreign objects instead of smobs. Remove
discussion of scm_must_malloc et al.
* doc/ref/guile.texi (API Reference): Rename SMOB menu item.
* doc/ref/libguile-snarf.texi (Function Snarfing): Update example to not
refer to smobs.
* doc/ref/tools.texi (How guile-snarf works): Likewise.
* libguile/hashtab.c (scm_make_doubly_weak_hash_table): Make 'size'
argument optional, like the weak hash table constructors.
* doc/ref/api-memory.texi (Weak hash tables): Document that 'size'
argument is optional for the weak hash table constructors.
* doc/ref/api-memory.texi (Weak vectors): In 'weak-vector?' entry, don't
claim that weak hash tables are weak vectors. Remove statement that
weak vectors are mainly useful for implementing weak hash tables.
* libguile/weaks.c (scm_is_weak_vector, scm_c_weak_vector_length):
(scm_c_weak_vector_ref, scm_c_weak_vector_set_x): New interfaces for
dealing with weak vectors from C.
(scm_weak_vector_length, scm_weak_vector_ref, scm_weak_vector_set_x):
New Scheme interfaces to weak vectors; to be used instead of
vector-length, vector-ref, etc.
* module/ice-9/weak-vector.scm: Export the new interfaces.
* doc/ref/api-memory.texi (Weak vectors): Document them.
* doc/ref/api-memory.texi (Garbage Collection
Functions)[scm_gc_protect_object]: Explain that it's equivalent to
storing in a global variable.
* doc/ref/api-smobs.texi (Smobs)[scm_set_smob_free]: Expand on the
relationship with `scm_gc_malloc ()'.
[scm_set_smob_mark]: Explain that it's usually not needed.
* scheme-compound.texi: Renamed to api-compound.texi.
* scheme-control.texi: Renamed to api-control.texi.
* scheme-data.texi: Renamed to api-data.texi.
* scheme-debug.texi: Renamed to api-debug.texi.
* deprecated.texi: Renamed to api-deprecated.texi.
* scheme-evaluation.texi: Renamed to api-evaluation.texi.
* ref-init.texi: Renamed to api-init.texi.
* scheme-io.texi: Renamed to api-io.texi.
* scheme-memory.texi: Renamed to api-memory.texi.
* scheme-modules.texi: Renamed to api-modules.texi.
* scheme-options.texi: Renamed to api-options.texi.
* scm.texi: Renamed to api-overview.texi.
* scheme-procedures.texi: Renamed to api-procedures.texi.
* scheme-scheduling.texi: Renamed to api-scheduling.texi.
* scheme-scm.texi: Renamed to api-scm.texi.
* scheme-smobs.texi: Renamed to api-smobs.texi.
* scheme-snarf.texi: Renamed to api-snarf.texi.
* scheme-translation.texi: Renamed to api-translation.texi.
* scheme-utility.texi: Renamed to api-utility.texi.
* debugging.texi: Renamed to scheme-debugging.texi.
* scripts.texi: Renamed to scheme-scripts.texi.
* program.texi: Renamed to libguile-program.texi.
