(* Title: Pure/PIDE/document.ML
Author: Makarius
Document as collection of named nodes, each consisting of an editable
list of commands, associated with asynchronous execution process.
*)
signature DOCUMENT =
sig
type id = int
type version_id = id
type command_id = id
type exec_id = id
val no_id: id
val create_id: unit -> id
val parse_id: string -> id
val print_id: id -> string
type edit = string * ((command_id * command_id option) list) option
type state
val init_state: state
val define_command: command_id -> string -> state -> state
val edit: version_id -> version_id -> edit list -> state -> (command_id * exec_id) list * state
val execute: version_id -> state -> state
end;
structure Document: DOCUMENT =
struct
(* unique identifiers *)
type id = int;
type version_id = id;
type command_id = id;
type exec_id = id;
val no_id = 0;
local
val id_count = Synchronized.var "id" 0;
in
fun create_id () =
Synchronized.change_result id_count
(fn i =>
let val i' = i + 1
in (i', i') end);
end;
val parse_id = Markup.parse_int;
val print_id = Markup.print_int;
fun err_dup kind id = error ("Duplicate " ^ kind ^ ": " ^ print_id id);
fun err_undef kind id = error ("Undefined " ^ kind ^ ": " ^ print_id id);
(** document structure **)
abstype entry = Entry of {next: command_id option, exec: exec_id option}
and node = Node of entry Inttab.table (*unique entries indexed by command_id, start with no_id*)
and version = Version of node Graph.T (*development graph wrt. static imports*)
with
(* command entries *)
fun make_entry next exec = Entry {next = next, exec = exec};
fun the_entry (Node entries) (id: command_id) =
(case Inttab.lookup entries id of
NONE => err_undef "command entry" id
| SOME (Entry entry) => entry);
fun put_entry (id: command_id, entry: entry) (Node entries) =
Node (Inttab.update (id, entry) entries);
fun put_entry_exec (id: command_id) exec node =
let val {next, ...} = the_entry node id
in put_entry (id, make_entry next exec) node end;
fun reset_entry_exec id = put_entry_exec id NONE;
fun set_entry_exec (id, exec_id) = put_entry_exec id (SOME exec_id);
(* iterate entries *)
fun fold_entries id0 f (node as Node entries) =
let
fun apply NONE x = x
| apply (SOME id) x =
let val entry = the_entry node id
in apply (#next entry) (f (id, entry) x) end;
in if Inttab.defined entries id0 then apply (SOME id0) else I end;
fun first_entry P node =
let
fun first _ NONE = NONE
| first prev (SOME id) =
let val entry = the_entry node id
in if P (id, entry) then SOME (prev, id, entry) else first (SOME id) (#next entry) end;
in first NONE (SOME no_id) end;
(* modify entries *)
fun insert_after (id: command_id) (id2: command_id) node =
let val {next, exec} = the_entry node id in
node
|> put_entry (id, make_entry (SOME id2) exec)
|> put_entry (id2, make_entry next NONE)
end;
fun delete_after (id: command_id) node =
let val {next, exec} = the_entry node id in
(case next of
NONE => error ("No next entry to delete: " ^ print_id id)
| SOME id2 =>
node |>
(case #next (the_entry node id2) of
NONE => put_entry (id, make_entry NONE exec)
| SOME id3 => put_entry (id, make_entry (SOME id3) exec) #> reset_entry_exec id3))
end;
(* node edits *)
type edit =
string * (*node name*)
((command_id * command_id option) list) option; (*NONE: remove, SOME: insert/remove commands*)
val empty_node = Node (Inttab.make [(no_id, make_entry NONE (SOME no_id))]);
fun edit_node (id, SOME id2) = insert_after id id2
| edit_node (id, NONE) = delete_after id;
(* version operations *)
fun nodes_of (Version nodes) = nodes;
val node_names_of = Graph.keys o nodes_of;
fun edit_nodes (name, SOME edits) (Version nodes) =
Version (nodes
|> Graph.default_node (name, empty_node)
|> Graph.map_node name (fold edit_node edits))
| edit_nodes (name, NONE) (Version nodes) = Version (Graph.del_node name nodes);
val empty_version = Version Graph.empty;
fun the_node version name =
Graph.get_node (nodes_of version) name handle Graph.UNDEF _ => empty_node;
fun put_node name node (Version nodes) =
Version (Graph.map_node name (K node) nodes); (* FIXME Graph.UNDEF !? *)
end;
(** global state -- document structure and execution process **)
abstype state = State of
{versions: version Inttab.table, (*version_id -> document content*)
commands: Toplevel.transition Inttab.table, (*command_id -> transition function*)
execs: Toplevel.state option lazy Inttab.table, (*exec_id -> execution process*)
execution: unit future list} (*global execution process*)
with
fun make_state (versions, commands, execs, execution) =
State {versions = versions, commands = commands, execs = execs, execution = execution};
fun map_state f (State {versions, commands, execs, execution}) =
make_state (f (versions, commands, execs, execution));
val init_state =
make_state (Inttab.make [(no_id, empty_version)],
Inttab.make [(no_id, Toplevel.empty)],
Inttab.make [(no_id, Lazy.value (SOME Toplevel.toplevel))],
[]);
(* document versions *)
fun define_version (id: version_id) version =
map_state (fn (versions, commands, execs, execution) =>
let val versions' = Inttab.update_new (id, version) versions
handle Inttab.DUP dup => err_dup "document version" dup
in (versions', commands, execs, execution) end);
fun the_version (State {versions, ...}) (id: version_id) =
(case Inttab.lookup versions id of
NONE => err_undef "document version" id
| SOME version => version);
(* commands *)
fun define_command (id: command_id) text =
map_state (fn (versions, commands, execs, execution) =>
let
val id_string = print_id id;
val tr =
Position.setmp_thread_data (Position.id_only id_string)
(fn () => Outer_Syntax.prepare_command (Position.id id_string) text) ();
val commands' =
Inttab.update_new (id, Toplevel.put_id id_string tr) commands
handle Inttab.DUP dup => err_dup "command" dup;
in (versions, commands', execs, execution) end);
fun the_command (State {commands, ...}) (id: command_id) =
(case Inttab.lookup commands id of
NONE => err_undef "command" id
| SOME tr => tr);
(* command executions *)
fun define_exec (id: exec_id) exec =
map_state (fn (versions, commands, execs, execution) =>
let val execs' = Inttab.update_new (id, exec) execs
handle Inttab.DUP dup => err_dup "command execution" dup
in (versions, commands, execs', execution) end);
fun the_exec (State {execs, ...}) (id: exec_id) =
(case Inttab.lookup execs id of
NONE => err_undef "command execution" id
| SOME exec => exec);
end;
(** editing **)
(* edit *)
local
fun is_changed node' (id, {next = _, exec}) =
(case try (the_entry node') id of
NONE => true
| SOME {next = _, exec = exec'} => exec' <> exec);
fun new_exec name (id: command_id) (exec_id, updates, state) =
let
val exec = the_exec state exec_id;
val exec_id' = create_id ();
val tr = Toplevel.put_id (print_id exec_id') (the_command state id);
val exec' =
Lazy.lazy (fn () =>
(case Lazy.force exec of
NONE => NONE
| SOME st => Toplevel.run_command name tr st));
val state' = define_exec exec_id' exec' state;
in (exec_id', (id, exec_id') :: updates, state') end;
in
fun edit (old_id: version_id) (new_id: version_id) edits state =
let
val old_version = the_version state old_id;
val new_version = fold edit_nodes edits old_version;
fun update_node name (rev_updates, version, st) =
let val node = the_node version name in
(case first_entry (is_changed (the_node old_version name)) node of
NONE => (rev_updates, version, st)
| SOME (prev, id, _) =>
let
val prev_exec = the (#exec (the_entry node (the prev)));
val (_, rev_upds, st') =
fold_entries id (new_exec name o #1) node (prev_exec, [], st);
val node' = fold set_entry_exec rev_upds node;
in (rev_upds @ rev_updates, put_node name node' version, st') end)
end;
(* FIXME proper node deps *)
val (rev_updates, new_version', state') =
fold update_node (node_names_of new_version) ([], new_version, state);
val state'' = define_version new_id new_version' state';
in (rev rev_updates, state'') end;
end;
(* execute *)
fun execute version_id state =
state |> map_state (fn (versions, commands, execs, execution) =>
let
val version = the_version state version_id;
fun force_exec NONE = ()
| force_exec (SOME exec_id) = ignore (Lazy.force (the_exec state exec_id));
val _ = List.app Future.cancel execution;
fun await_cancellation () = uninterruptible (fn _ => Future.join_results) execution;
val execution' = (* FIXME proper node deps *)
node_names_of version |> map (fn name =>
Future.fork_pri 1 (fn () =>
(await_cancellation ();
fold_entries no_id (fn (_, {exec, ...}) => fn () => force_exec exec)
(the_node version name) ())));
in (versions, commands, execs, execution') end);
end;