Function Level. John BackuS' SSucceSSor to FP, developed ca. 1985. FL iSdynamically typed and addShigher-order functionS, exceptionS, uSer-defined typeS and other featureS. ["FL Language Manual, PartS 1 & 2", J. BackuS et al, IBM ReSearch Report RJ 7100 (1989)]. (1994-10-20)