Hi, I had a chat with Kenn at Flink Forward and he did an off-hand remark about how it might be better if triggers where not allowed to mark a window as finished and instead always be "Repeatedly" (if I understood correctly).
Maybe you (Kenn) could go a bit more in depth about what you meant by this and if we should actually change this in Beam. Would this mean that we then have the opposite of Repeatedly, i.e. Once, or Only.once(T)? I also noticed some inconsistencies in when triggers behave as repeated triggers and once triggers. For example, AfterPane.elementCountAtLeast(5) only fires once if used alone but it it fires repeatedly if used as the speculative trigger in AfterWatermark.pastEndOfWindow().withEarlyFirings(...). (This is true for all "once" triggers.) Cheers, Aljoscha
