Reduce is a function or method that is used to take the values in an array or a list and apply a function to successive members of the list to produce (or reduce them to), a single value.



Task

Show how reduce (or foldl or foldr etc), work (or would be implemented) in your language.



See also

 Wikipedia article:   Fold
 Wikipedia article:   Catamorphism


lreduce(f, [a, b, c, d], x0);
/* (%o1)                     f(f(f(f(x0, a), b), c), d) */