thread and task support

Stream: general

[Xinrun Miao]

Hello everyone! I noticed we have a page in lean 4 manual but it's still blank right now. Does lean already support multi-threaded programming now? I am very excited about this feature

[Siddhartha Gadgil]

Yes indeed it does with Tasks.

[Henrik Böving]

Note that the Task feature and the surrounding APIs are far from being a full thread eco system since we are missing a lot of other primitives that would be interesting. But you can certainly do quite a bit already