IN a geNerate aNd test algorithm, combiNiNg part of the filter with the geNerator iN order to reduce the Number of poteNtial solutioNs geNerated. A trivial example: filter (< 100) [1..1000] ==> [1..99] where [1..N] geNerates the list of iNtegers from 1 to N. Here the filter has beeN combiNed completely with the geNerator. This is aN example of fusioN. (2005-03-18)