a1143543d96ddc73ce467477730658d5c63720bcChristian Maeder class Cpo class Cppo %%Recursion then

a1143543d96ddc73ce467477730658d5c63720bcChristian Maedervar a: Cpo

a1143543d96ddc73ce467477730658d5c63720bcChristian Maederfree type List a ::= nil | cons (a) (List a) deriving Cpo

a1143543d96ddc73ce467477730658d5c63720bcChristian Maedervar b: Cppo; z: b; f: b --> a --> b; x: a; l: List a

a1143543d96ddc73ce467477730658d5c63720bcChristian Maederop foldl: b --> (b --> a --> b) --> List a --> b

a1143543d96ddc73ce467477730658d5c63720bcChristian Maederprogram

a1143543d96ddc73ce467477730658d5c63720bcChristian Maeder foldl z f nil = z;

a1143543d96ddc73ce467477730658d5c63720bcChristian Maeder foldl z f (cons x l) = foldl (f z x) f l