1sig  maps.
2
3kind  i  type.
4
5type  father  i -> i -> o.
6
7type  jane    i.
8type  moses   i.
9type  john    i.
10type  peter   i.
11type  james   i.
12type  charles i.
13
14type	mapfun		list A -> (A -> B) -> list B -> o.
15type	mappred		list A -> (A -> B -> o) -> list B -> o.
16type	reduce		list A -> (A -> B -> B) -> B -> B -> o.
17type	reduce_eval	list A -> (A -> B -> B) -> B -> B -> o.
18type	reduce_pred	list A -> (A -> B -> o) -> (B -> B -> B) -> B -> o.
19type	for_each	list A -> (A -> o) -> o.
20
21% for testing
22type   a  i.
23type   b  i.
24type   g  i -> i -> i.