Hi.
I've now implemented the new rehash behaviour that we discussed
during the conference ~2 months ago. This means that weak mappings
that contain the only reference to a reference-counted object will
free the object when the hashtable is resized. Note that this only
takes care of the most common case of weak mappings. The more
complicated cases will still need the full gc.
For reference:
INDEX INDEX VALUE VALUE HANDLING
REFTYPE CONTENT REFTYPE CONTENT
------------------------------------------
STRONG * STRONG * KEEP
STRONG * WEAK UNREF KEEP
STRONG * WEAK SINGLE FREE
STRONG * WEAK MULTIPLE KEEP
WEAK UNREF STRONG * KEEP
WEAK SINGLE STRONG * FREE
WEAK MULTIPLE STRONG * KEEP
WEAK UNREF WEAK UNREF KEEP
WEAK UNREF WEAK MULTIPLE KEEP
WEAK SINGLE WEAK * FREE
WEAK * WEAK SINGLE FREE
WEAK MULTIPLE WEAK UNREF KEEP
WEAK MULTIPLE WEAK MULTIPLE KEEP
Legend:
STRONG Strong (default) reference.
WEAK Weak (set with set_weak_flag()) reference.
* Any value.
UNREF Value that is not reference counted (eg ints or floats).
SINGLE Reference-counted value with a single reference.
MULTIPLE Reference-counted value with more than one reference.
KEEP Entry to be kept after the rehash.
FREE Entry to be freed during the rehash.
I would appreciate testing, and any comments about the behaviour
(intended or otherwise).
Happy New Year!
/grubba
