Hi, I am generating code coverage reports using hpc, it works great. The reports would be much more helpful if I could somehow tell hpc to treat certain expressions as "covered" though. As an example, let's think of "impossible" cases of a function. f x | check x = result x | otherwise = error "impossible" I know there are techniques to get rid of (or minimise the number of) the impossible cases. I also can see how this information can be relevant, i.e. seeing whether `check` always holds or not in the report. However, at least for one version of the report, I want the error call like the above example to be treated as covered. Or maybe a different colour could be used to annotate "ignored"? Did anyone need/want anything like this? Is it possible? My guess is that this is somewhat possible using manually generated .tix files and merging them with the .tix file that is generated in the usual way. However this feels too adhoc, fragile and seems to be too much effort to reach a simple goal. Best, Ozgur