I was looking for a way to highlight lines above the cursor line to mark them as done, whatever that means in the context of what I'm doing.
I came up with this
match Comment /\_.*\%#.*/ or, in words, highlight everything including newlines up until the cursor character, and then the rest of the line too as comment text
This does the job and allows me to easily progress through a document/source file by moving the cursor down, but the problem is: It's slow. REALLY slow.
Is there some better way to achieve the same result? I don't mind it involving a lot of magic, since I will most likely hide it away behind a function in my vimrc anyway, but I am restricted to only vimscript.