I actually did code hinting for PHP in a fairly popular commercial product, more than 10 years ago - and I disagree with you that it has to be less capable. You

I actually did code hinting for PHP in a fairly popular commercial product, more than 10 years ago - and I disagree with you that it has to be less capable. You can use heuristics - people are forgiving because they understand you can't get everything right. You can use configuration files & user hints to help the semantic analysis. You can absolutely get the hints mostly right - and it's automatic, so probably closer to being correct than anything that'd have to be maintained by hand.