The thing this appears to be missing is the ability to capture the part of the stack between the try and hurl as a first-class value and reify it later, althoug

The thing this appears to be missing is the ability to capture the part of the stack between the try and hurl as a first-class value and reify it later, although the toss/return is not too dissimilar as toss does capture the stack and return reifies it. It's close to multi-prompt due to multiple catch branches, so I would describe it as a one-shot, multi-prompt, second-class delimited continuation. A bit more powerful are multi-shot, multi-prompt, first-class delimited continuations, which you can then use to implement exceptions themselves with multiple catch blocks.