G'day all.
Quoting Luke Palmer
What do you mean by "black hole" here?
A "black hole" is what happens when evalation of something recursively depends on its own evaluation in such a way that no useful work can be done. An example is: let omega = omega + 1 in omega In previous GHCs, that triggered am error which used the phrase "black hole". Now, I think it just consumes the heap and/or stack. On my 2005-era Hugs, it causes a seg fault. Most examples of black holes aren't so blatant. In all cases, they are genuine bugs in the program (i.e. the program is incorrect), but programs containing bugs like this are not even expressible in a strict language. So I claim this is a class of (admittedly rare) bug that is only a problem because of laziness. Cheers, Andrew Bromage