split-lines | Split lines into an array of lines | Icon library

It is rather simple to check intersection of two LineString objects. To avoid getting empty geometries, I suggest to check for intersection first before computing it. Something like this:

What you've got so far (slightly rewritten) is:

Consider this:

The problem is that process-async returns immediately with "[...] a channel which will receive the result of the body when completed" (since go-loop is just syntactic sugar for (go (loop ...)) and go returns immediately).

This means that the blocking in async-blocker will have a value almost immediately and the order in which the go blocks from process-async and async-blocker get executed is undetermined. It might be that most of the time the block from process-async executes first because it gets created first, but that is not much of a guarantee in a concurrent context.