It doesn't. Nothing does. Good poker players should have no problem doing all this in their heads. The tooling which does help is hand analysis and replay. I haven't kept up, but there used to be tools while playing online poker which would track your play and the play of your opponents. Then I believe there were databases where you could upload that information so that you could study the play of regular opponents. Most helpful was looking at your own play though.

I doubt it’s supposed to, it’s to calculate who wins when writing your own poker implementation. I am not the author, but calculating the winner is non trivial.

Is it not? The win criteria is well specified so just iterate downwards from the highest priority win until you find a match?

Sure, but that gets complicated when comparing two matching hands (flush vs flush, 2 pair vs 2pair). It’s more than a 50 line problem to solve.

Okay fair it’s more than 50 lines, I guess my definition of non-trivial is something you can’t quickly think of a design for. I’ll try it later and see if there’s some gotchas I can’t think of :)

I had the same initial reaction as the other person. Should be easy right? I think you’re right though, there are probably many more steps to getting this right than it seems on the surface.

I kind of want to take your 50 line challenge however :) I always loved playing poker, might be a fun exercise.