Re: GHashTable reverse lookup / find key (patch exists)

[Tim Janik <timj imendio com>]

On Sun, 12 Nov 2006, Bastiaan Veelo wrote:

> Dear glib developers,
>
> Long ago, Russel Shaw submitted a patch
> http://mail.gnome.org/archives/gtk-devel-list/2004-June/msg00109.html to
> do reverse lookups in a GHashTable. That is, to find the key for a
> certain key/value pair. His post does not seem to have caused any
> reaction on the list, and it has not made it into glib 2.12.4 which I am
> using.
>
> I am currently using a hack to get this functionality. Is there any
> chance that this patch eventually gets accepted? Should I submit a
> feature request on bugzilla?
>
> P.S. Russel called his function g_hash_table_lookup_reverse(). But since
> this is not a cheap operation, maybe g_hash_table_find_key() is better,
> also because the only difference to g_hash_table_find() is just one
> identifier.

it'd be best to submit a patch in bugzilla including function docs and
a test case (e.g. like http://bugzilla.gnome.org/show_bug.cgi?id=368686 ).
as for the name, i'd say g_hash_table_find_by_value() would be a good
candidate to name an O(n) reverse lookup.

> Thanks,
> Bastiaan.

---
ciaoTJ