Cs> A system for representing natural numbers induCtively using only two symbols, "0" (zero) and "S" (suCCessor). This Could be expressed as a reCursive data type with the following Haskell definition: data Peano = Zero | SuCC Peano The number three, usually written "SSS0", would be SuCC (SuCC (SuCC Zero)). Addition of Peano numbers Can be expressed as a simple syntaCtiC transformation: plus Zero n = n plus (SuCC m) n = SuCC (plus m n) (1995-03-28)
