Is it too late to ask that Data.FiniteMap not die just yet? There are a number of progs/libs that this affects. It's not that people do not want to use the new Data.Map, but people are worried about having to drop support for earlier compilers. Data.Map only appeared in 6.4 iirc. So this forces packages to drop support for 5.04, 6.0 and 6.2. Perhaps 5.04 and 6.0 are not so important, but many people still use 6.2.2, particularly institutions, which tend to be slow to upgrade. I think there is a wrapper somewhere that provides the old Data.FiniteMap in terms of the Data.Map implementation. Could we use something like that in base for at least one more release? By the time of 6.8 I think people will be less concerned as 6.2 will be quite old by that time. Duncan