Marc: I tried to declare (not block) in a long list of declarations and was told: > (compile-file "pixel-method") *** ERROR IN "/Volumes/lucier/text/papers/b-one-infinity/programs/ pixel-method5/generic-arrays.scm"@1294.1 -- Declaration can't be negated #f leaving me to guess which of my (not ...) declarations could not be negated. Brad