Well he answered me as if he understood me, so I am going to go ahead with that assumption. This thread is not at all difficult to follow. Anyone who uses rescue should be shot on sight--it takes a masochist to introduce panic as a stack unwind mechanism intended to be caught. The process should stop. I have never seen rescue used in the wild, so it seems as if the only thing this has in common with exceptions is stack unwinding. It is apples and oranges and the performance difference is meaningless unless you try to use them as the same.

To be fair, pcwalton was not advocating this. He was pointing out that defer is already more costly runtime wise than exceptions, correcting another person.

I disagree completely. We're talking about a feature that can affect the execution path of your code even if you're not using it yourself. For such a feature, you have to work under the assumption that someone will be using it somewhere and you have to deal with it.

The whole reasoning behind not supporting a ton of features in Go is that excuses like "don't need it? Don't use it!" are invalid when it comes to programming language features. And nowhere is this more relevant than for a feature that can unwind the stack without warning.