A different semantics for WeakMap#get default value

Andrea Giammarchi andrea.giammarchi at gmail.com
Thu Jan 19 09:24:48 PST 2012

On Thu, Jan 19, 2012 at 6:11 PM, Mark S. Miller <erights at google.com> wrote:
> That's not quite true in the collection I posted, since an InfiniteMap is
> only *initially* total. It still emulates deletes by using tombstones to
> poke holes into its initially universal domain. When doing a get at a
> deleted key, the defaultValue would come into effect.

got it, my concern was mainly about the very first case where defaultValue
is not even considered and we have two completely different behaviors if we
get before or after a key has been set ... no way to use the lazyFactory(key,
defaultValue) { ... do stuff and return defaultValue }, if necessary, in
order to be able to instantly set that default ( I just find weird this
"need to delete first, then get default after" )

Hope you got what I mean

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