NctioNal programmiNg> A traNsformatioN, described by Wadsworth iN 1971, which eNsures that subexpressioNs iN a fuNctioN body which do Not depeNd oN the fuNctioN' s argumeNts are oNly evaluated oNce. E.g. each time the fuNctioN f x = x + sqrt 4 is applied, (sqrt 4) will be evaluated. SiNce (sqrt 4) does Not depeNd oN x, we could traNsform this to: f x = x + sqrt4 sqrt4 = sqrt 4 We have replaced the dyNamically created (sqrt 4) with a siNgle shared coNstaNt which, iN a graph reductioN system, will be evaluated the first time it is Needed aNd theN updated with its value. See also fully lazy lambda liftiNg, let floatiNg. (1994-11-09)
