ocaml-containers/src/data/CCKTree.mli
2020-07-23 16:32:52 +02:00

144 lines
4.1 KiB
OCaml

(* This file is free software, part of containers. See file "license" for more details. *)
(** {1 Lazy Tree Structure}
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. *)
type 'a iter = ('a -> unit) -> unit
type 'a gen = unit -> 'a option
type 'a printer = Format.formatter -> 'a -> unit
(** {2 Basics} *)
type +'a t = unit -> [`Nil | `Node of 'a * 'a t list]
val empty : 'a t
val is_empty : _ t -> bool
val singleton : 'a -> 'a t
(** Tree with only one label. *)
val node : 'a -> 'a t list -> 'a t
(** Build a node from a label and a list of children. *)
val node1 : 'a -> 'a t -> 'a t
(** Node with one child. *)
val node2 : 'a -> 'a t -> 'a t -> 'a t
(** Node with two children. *)
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 size : _ t -> int
(** Number of elements. *)
val height : _ t -> int
(** Length of the longest path to empty leaves. *)
val map : ('a -> 'b) -> 'a t -> 'b t
val (>|=) : 'a t -> ('a -> 'b) -> 'b t
val cut_depth : int -> 'a t -> 'a t
(** Cut the tree at the given depth, so it becomes finite. *)
(** {2 Graph Traversals} *)
(** Abstract Set structure *)
class type ['a] pset = object
method add : 'a -> 'a pset
method mem : 'a -> bool
end
val set_of_cmp : cmp:('a -> 'a -> int) -> unit -> 'a pset
(** Build a set structure given a total ordering. *)
val dfs : pset:'a pset -> 'a t -> [ `Enter of 'a | `Exit of 'a ] Seq.t
(** Depth-first traversal of the tree. *)
val bfs : pset:'a pset -> 'a t -> 'a Seq.t
(** Breadth-first traversal of the tree. *)
val force : 'a t -> ([ `Nil | `Node of 'a * 'b list ] as 'b)
(** [force t] evaluates [t] completely and returns a regular tree
structure.
@since 0.13 *)
val find : pset:'a pset -> ('a -> 'b option) -> 'a t -> 'b option
(** Look for an element that maps to [Some _]. *)
(** {2 Pretty-printing}
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);;
]}
*)
val pp : 'a printer -> 'a t printer
(** A pretty-printer using S-expressions and boxes to render the tree.
Empty nodes are not rendered; sharing is ignored.
@since 0.9 *)
(** {2 Pretty printing in the DOT (graphviz) format} *)
module Dot : sig
type attribute = [
| `Color of string
| `Shape of string
| `Weight of int
| `Style of string
| `Label of string
| `Id of string (** Unique ID in the graph. Allows sharing. *)
| `Other of string * string
] (** Dot attributes for nodes *)
type graph = (string * attribute list t list)
(** A dot graph is a name, plus a list of trees labelled with attributes *)
val mk_id : ('a, Buffer.t, unit, attribute) format4 -> 'a
(** Using a formatter string, build an ID. *)
val mk_label : ('a, Buffer.t, unit, attribute) format4 -> 'a
(** Using a formatter string, build a label. *)
val make : name:string -> attribute list t list -> graph
val singleton : name:string -> attribute list t -> graph
val pp_single : string -> attribute list t printer
val pp : graph printer
(** Printer to DOT with indentation, etc.
@since 0.6.1 *)
val print_to_file : string -> graph -> unit
(** [print_to_file filename g] prints [g] into a file whose name
is [filename].
@since 0.6.1 *)
val to_file : ?name:string -> string -> attribute list t list -> unit
(** [to_file filename trees] makes a graph out of the trees, opens the
file [filename] and prints the graph into the file.
@param name name of the graph.
@since 0.6.1 *)
end