I remembered doing an "easier" kata with this same problem that had square brackets as well as curly braces that used this same method so I tried replicating it off memory and I ended up with something a little more complicated. Seems I forgot to include the stack.pop() in the else if statement and went a roundabout way.

All this to say that I like this method much better than the regex ones.

Yeesh, why do I always have to make things so complicated.

Ah, that makes sense. Thanks for the explanation!

Ah, that's how you make it DRYer, thanks for this!