really simple blocks just defined like this:
from that you get similar functionality to the catch and throw blocks from "Iteration, composition" library (previously in the variadic if library iirc), except implemented using very questionable behaviour of the report block when used inside run (see my bug report)
it doesn't use continuations (like the official throw/catch blocks) or errors (like in the "Catch errors" library) which are both much more intended ways of implementing flow control
so you can essentially report a value all the way through multiple custom blocks:
don't rely on this in any projects i'm just messing with a feature that i don't think should exist interesting undefined behaviour :3