Julia: please implement rand for IntSet

[jsams]

I'm on an official build of 0.6.2, and it doesn't seem to be available.

rand(IntSet(1:10))

throws "ERROR: MethodError: no method matching rand(::IntSet)"

Seems like IntSet is just a wrapper over a bitfield of true/false values? Not sure what a fast O(1) would look like for that, but it would be nice to have available!

[mtsch]

Hey,
I would like to work on this, if it can wait until Friday or the weekend. I'm not sure it can be really done in O(1), but I can do better than rand(collect(.)).

[jsams]

Incidentally, in my context, I actually need to sample from both the true and false values. When you figure out how to do this for the usual scenario of sampling from the true values, I would appreciate if you could comment on how to modify that for sampling from the false values if you have time. Thanks!

[mtsch]

So I played around with this and have an implementation for 0.6 ready, but I realized rand(::IntSet) is already defined on master.

If that is desired, I can add it as a fix for the next release of Julia v0.6, but I need some guidance on how to make a pull request for an old version.

Either way, @jsams, you can send me an email (so we don't spam this issue) and I can send you the code, or help you come up with something more efficient for your specific use case.

[fredrikekre]

So then this issue can be considered fixed by dd6a94ab21dac82b2157730bbf3399f499050fc7 (#25029).

I can add it as a fix for the next release of Julia v0.6, but I need some guidance on how to make a pull request for an old version.

v0.6 are not getting any more features, besides, it is unlikely that there will be another release in the 0.6 series.