This structure can be used to represent trees and directed graphs (as infinite trees) in a lazy fashion. Like CCKList, it is a structural type.
val empty : 'a t
val is_empty : _ t ‑> bool
val fold : ('a ‑> 'b ‑> 'a) ‑> 'a ‑> 'b t ‑> 'a
Fold on values in no specified order. May not terminate if the tree is infinite.
val iter : ('a ‑> unit) ‑> 'a t ‑> unit
val set_of_cmp : cmp:('a ‑> 'a ‑> int) ‑> unit ‑> 'a pset
Build a set structure given a total ordering.
val force : 'a t ‑> [ `Nil | `Node of 'a * 'b list ] as b
force t
evaluates t
completely and returns a regular tree
structure.
Example (tree of calls for naive Fibonacci function):
let mk_fib n =
let rec fib' l r i =
if i=n then r else fib' r (l+r) (i+1)
in fib' 1 1 1;;
let rec fib n = match n with
| 0 | 1 -> CCKTree.singleton (`Cst n)
| _ -> CCKTree.node2 (`Plus (mk_fib n)) (fib (n-1)) (fib (n-2));;
let pp_node fmt = function
| `Cst n -> Format.fprintf fmt "%d" n
| `Plus n -> Format.fprintf fmt "%d" n;;
Format.printf "%a@." (CCKTree.pp pp_node) (fib 8);;
A pretty-printer using S-expressions and boxes to render the tree. Empty nodes are not rendered; sharing is ignored.
module Dot : sig ... end