(* Copyright (C) 2004-2005, HELM Team.
*
* This file is part of HELM, an Hypertextual, Electronic
* Library of Mathematics, developed at the Computer Science
* Department, University of Bologna, Italy.
*
* HELM is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* HELM is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with HELM; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston,
* MA 02111-1307, USA.
*
* For details, see the HELM World-Wide-Web page,
* http://cs.unibo.it/helm/.
*)
(* $Id$ *)
open Printf
open GrafiteTypes
open MatitaGtkMisc
open MatitaGuiTypes
open CicMathView
module Stack = Continuationals.Stack
let cicBrowsers = ref []
let tab_label meta_markup =
let rec aux =
function
| `Closed m -> sprintf "%s" (aux m)
| `Current m -> sprintf "%s" (aux m)
| `Shift (pos, m) -> sprintf "|%d: %s" pos (aux m)
| `Meta n -> sprintf "?%d" n
in
let markup = aux meta_markup in
(GMisc.label ~markup ~show:true ())#coerce
let goal_of_switch = function Stack.Open g | Stack.Closed g -> g
class sequentsViewer ~(notebook:GPack.notebook) ~(cicMathView:cicMathView) () =
object (self)
method cicMathView = cicMathView (** clickableMathView accessor *)
val mutable pages = 0
val mutable switch_page_callback = None
val mutable page2goal = [] (* associative list: page no -> goal no *)
val mutable goal2page = [] (* the other way round *)
val mutable goal2win = [] (* associative list: goal no -> scrolled win *)
val mutable _metasenv = [],[]
val mutable scrolledWin: GBin.scrolled_window option = None
(* scrolled window to which the sequentViewer is currently attached *)
val logo = (GMisc.image
~file:(MatitaMisc.image_path "matita_medium.png") ()
:> GObj.widget)
val logo_with_qed = (GMisc.image
~file:(MatitaMisc.image_path "matita_small.png") ()
:> GObj.widget)
method load_logo =
notebook#set_show_tabs false;
ignore(notebook#append_page logo)
method load_logo_with_qed =
notebook#set_show_tabs false;
ignore(notebook#append_page logo_with_qed)
method reset =
cicMathView#remove_selections;
(match scrolledWin with
| Some w ->
(* removing page from the notebook will destroy all contained widget,
* we do not want the cicMathView to be destroyed as well *)
w#remove cicMathView#coerce;
scrolledWin <- None
| None -> ());
(match switch_page_callback with
| Some id ->
GtkSignal.disconnect notebook#as_widget id;
switch_page_callback <- None
| None -> ());
for i = 0 to pages do notebook#remove_page 0 done;
notebook#set_show_tabs true;
pages <- 0;
page2goal <- [];
goal2page <- [];
goal2win <- [];
_metasenv <- [],[]
method nload_sequents : 'status. #GrafiteTypes.status as 'status -> unit
= fun (status : #GrafiteTypes.status) ->
let _,_,metasenv,subst,_ = status#obj in
_metasenv <- metasenv,subst;
pages <- 0;
let win goal_switch =
let w =
GBin.scrolled_window ~hpolicy:`AUTOMATIC ~vpolicy:`ALWAYS
~shadow_type:`IN ~show:true () in
let reparent () =
scrolledWin <- Some w;
(match cicMathView#misc#parent with
| None -> ()
| Some parent ->
let parent =
match cicMathView#misc#parent with
None -> assert false
| Some p -> GContainer.cast_container p
in
parent#remove cicMathView#coerce);
w#add cicMathView#coerce
in
goal2win <- (goal_switch, reparent) :: goal2win;
w#coerce
in
assert (
let stack_goals = Stack.open_goals status#stack in
let proof_goals = List.map fst metasenv in
if
HExtlib.list_uniq (List.sort Pervasives.compare stack_goals)
<> List.sort Pervasives.compare proof_goals
then begin
prerr_endline ("STACK GOALS = " ^ String.concat " " (List.map string_of_int stack_goals));
prerr_endline ("PROOF GOALS = " ^ String.concat " " (List.map string_of_int proof_goals));
false
end
else true
);
let render_switch =
function Stack.Open i ->`Meta i | Stack.Closed i ->`Closed (`Meta i)
in
let page = ref 0 in
let added_goals = ref [] in
(* goals can be duplicated on the tack due to focus, but we should avoid
* multiple labels in the user interface *)
let add_tab markup goal_switch =
let goal = Stack.goal_of_switch goal_switch in
if not (List.mem goal !added_goals) then begin
ignore(notebook#append_page
~tab_label:(tab_label markup) (win goal_switch));
page2goal <- (!page, goal_switch) :: page2goal;
goal2page <- (goal_switch, !page) :: goal2page;
incr page;
pages <- pages + 1;
added_goals := goal :: !added_goals
end
in
let add_switch _ _ (_, sw) = add_tab (render_switch sw) sw in
Stack.iter (** populate notebook with tabs *)
~env:(fun depth tag (pos, sw) ->
let markup =
match depth, pos with
| 0, 0 -> `Current (render_switch sw)
| 0, _ -> `Shift (pos, `Current (render_switch sw))
| 1, pos when Stack.head_tag status#stack = `BranchTag ->
`Shift (pos, render_switch sw)
| _ -> render_switch sw
in
add_tab markup sw)
~cont:add_switch ~todo:add_switch
status#stack;
switch_page_callback <-
Some (notebook#connect#switch_page ~callback:(fun page ->
let goal_switch =
try List.assoc page page2goal with Not_found -> assert false
in
self#render_page status ~page ~goal_switch))
method private render_page:
'status. #ApplyTransformation.status as 'status -> page:int ->
goal_switch:Stack.switch -> unit
= fun status ~page ~goal_switch ->
(match goal_switch with
| Stack.Open goal ->
let menv,subst = _metasenv in
cicMathView#nload_sequent status menv subst goal
| Stack.Closed goal ->
let root = Lazy.force closed_goal_mathml in
cicMathView#load_root ~root);
(try
cicMathView#set_selection None;
List.assoc goal_switch goal2win ();
(match cicMathView#misc#parent with
None -> assert false
| Some p ->
(* The text widget dinamycally inserts the text in a separate
thread. We need to wait for it to terminate before we can
move the scrollbar to the end *)
while Glib.Main.pending()do ignore(Glib.Main.iteration false); done;
let w =
new GBin.scrolled_window
(Gobject.try_cast p#as_widget "GtkScrolledWindow") in
(* The double change upper/lower is to trigger the emission of
changed :-( *)
w#hadjustment#set_value w#hadjustment#upper;
w#hadjustment#set_value w#hadjustment#lower;
w#vadjustment#set_value w#vadjustment#lower;
w#vadjustment#set_value
(w#vadjustment#upper -. w#vadjustment#page_size));
with Not_found -> assert false)
method goto_sequent: 'status. #ApplyTransformation.status as 'status -> int -> unit
= fun status goal ->
let goal_switch, page =
try
List.find
(function Stack.Open g, _ | Stack.Closed g, _ -> g = goal)
goal2page
with Not_found -> assert false
in
notebook#goto_page page;
self#render_page status ~page ~goal_switch
end
let blank_uri = BuildTimeConf.blank_uri
let current_proof_uri = BuildTimeConf.current_proof_uri
type term_source =
[ `Ast of NotationPt.term
| `NCic of NCic.term * NCic.context * NCic.metasenv * NCic.substitution
| `String of string
]
class cicBrowser_impl ~(history:MatitaTypes.mathViewer_entry MatitaMisc.history)
()
=
let uri_RE =
Pcre.regexp
"^cic:/([^/]+/)*[^/]+\\.(con|ind|var)(#xpointer\\(\\d+(/\\d+)+\\))?$"
in
let dir_RE = Pcre.regexp "^cic:((/([^/]+/)*[^/]+(/)?)|/|)$" in
let is_uri txt = Pcre.pmatch ~rex:uri_RE txt in
let is_dir txt = Pcre.pmatch ~rex:dir_RE txt in
let gui = MatitaMisc.get_gui () in
let win = new MatitaGeneratedGui.browserWin () in
let _ = win#browserUri#misc#grab_focus () in
let gviz = LablGraphviz.graphviz ~packing:win#graphScrolledWin#add () in
let searchText =
GSourceView2.source_view ~auto_indent:false ~editable:false ()
in
let _ =
win#scrolledwinContent#add (searchText :> GObj.widget);
let callback () =
let text = win#entrySearch#text in
let highlight start end_ =
searchText#source_buffer#move_mark `INSERT ~where:start;
searchText#source_buffer#move_mark `SEL_BOUND ~where:end_;
searchText#scroll_mark_onscreen `INSERT
in
let iter = searchText#source_buffer#get_iter `SEL_BOUND in
match iter#forward_search text with
| None ->
(match searchText#source_buffer#start_iter#forward_search text with
| None -> ()
| Some (start,end_) -> highlight start end_)
| Some (start,end_) -> highlight start end_
in
ignore(win#entrySearch#connect#activate ~callback);
ignore(win#buttonSearch#connect#clicked ~callback);
in
let toplevel = win#toplevel in
let mathView = cicMathView ~packing:win#scrolledBrowser#add () in
let fail message =
MatitaGtkMisc.report_error ~title:"Cic browser" ~message
~parent:toplevel ()
in
let tags =
[ "dir", GdkPixbuf.from_file (MatitaMisc.image_path "matita-folder.png");
"obj", GdkPixbuf.from_file (MatitaMisc.image_path "matita-object.png") ]
in
let b = (not (Helm_registry.get_bool "matita.debug")) in
let handle_error f =
try
f ()
with exn ->
if b then
fail (snd (MatitaExcPp.to_string exn))
else raise exn
in
let handle_error' f = (fun () -> handle_error (fun () -> f ())) in
let load_easter_egg = lazy (
win#browserImage#set_file (MatitaMisc.image_path "meegg.png"))
in
let load_hints () =
let module Pp = GraphvizPp.Dot in
let filename, oc = Filename.open_temp_file "matita" ".dot" in
let fmt = Format.formatter_of_out_channel oc in
let status = (get_matita_script_current ())#status in
Pp.header
~name:"Hints"
~graph_type:"graph"
~graph_attrs:["overlap", "false"]
~node_attrs:["fontsize", "9"; "width", ".4";
"height", ".4"; "shape", "box"]
~edge_attrs:["fontsize", "10"; "len", "2"] fmt;
NCicUnifHint.generate_dot_file status fmt;
Pp.trailer fmt;
Pp.raw "@." fmt;
close_out oc;
gviz#load_graph_from_file ~gviz_cmd:"neato -Tpng" filename;
(*HExtlib.safe_remove filename*)
in
let load_coerchgraph tred () =
let module Pp = GraphvizPp.Dot in
let filename, oc = Filename.open_temp_file "matita" ".dot" in
let fmt = Format.formatter_of_out_channel oc in
Pp.header
~name:"Coercions"
~node_attrs:["fontsize", "9"; "width", ".4"; "height", ".4"]
~edge_attrs:["fontsize", "10"] fmt;
let status = (get_matita_script_current ())#status in
NCicCoercion.generate_dot_file status fmt;
Pp.trailer fmt;
Pp.raw "@." fmt;
close_out oc;
if tred then
gviz#load_graph_from_file
~gviz_cmd:"dot -Txdot | tred |gvpack -gv | dot" filename
else
gviz#load_graph_from_file
~gviz_cmd:"dot -Txdot | gvpack -gv | dot" filename;
HExtlib.safe_remove filename
in
object (self)
val mutable gviz_uri = NReference.reference_of_string "cic:/dummy.dec";
val dep_contextual_menu = GMenu.menu ()
initializer
win#mathOrListNotebook#set_show_tabs false;
win#browserForwardButton#misc#set_sensitive false;
win#browserBackButton#misc#set_sensitive false;
ignore (win#browserUri#connect#activate (handle_error' (fun () ->
self#loadInput win#browserUri#text)));
ignore (win#browserHomeButton#connect#clicked (handle_error' (fun () ->
self#load (`About `Current_proof))));
ignore (win#browserRefreshButton#connect#clicked
(handle_error' (self#refresh ~force:true)));
ignore (win#browserBackButton#connect#clicked (handle_error' self#back));
ignore (win#browserForwardButton#connect#clicked
(handle_error' self#forward));
ignore (win#toplevel#event#connect#delete (fun _ ->
let my_id = Oo.id self in
cicBrowsers := List.filter (fun b -> Oo.id b <> my_id) !cicBrowsers;
false));
ignore(win#whelpResultTreeview#connect#row_activated
~callback:(fun _ _ ->
handle_error (fun () -> self#loadInput (self#_getSelectedUri ()))));
mathView#set_href_callback (Some (fun uri ->
handle_error (fun () ->
let uri = `NRef (NReference.reference_of_string uri) in
self#load uri)));
gviz#connect_href (fun button_ev attrs ->
let time = GdkEvent.Button.time button_ev in
let uri = List.assoc "href" attrs in
gviz_uri <- NReference.reference_of_string uri;
match GdkEvent.Button.button button_ev with
| button when button = MatitaMisc.left_button -> self#load (`NRef gviz_uri)
| button when button = MatitaMisc.right_button ->
dep_contextual_menu#popup ~button ~time
| _ -> ());
connect_menu_item win#browserCloseMenuItem (fun () ->
let my_id = Oo.id self in
cicBrowsers := List.filter (fun b -> Oo.id b <> my_id) !cicBrowsers;
win#toplevel#misc#hide(); win#toplevel#destroy ());
connect_menu_item win#browserUrlMenuItem (fun () ->
win#browserUri#misc#grab_focus ());
self#_load (`About `Blank);
toplevel#show ()
val mutable current_entry = `About `Blank
(** @return None if no object uri can be built from the current entry *)
method private currentCicUri =
match current_entry with
| `NRef uri -> Some uri
| _ -> None
val model =
new MatitaGtkMisc.taggedStringListModel tags win#whelpResultTreeview
val mutable lastDir = "" (* last loaded "directory" *)
method mathView = mathView
method private _getSelectedUri () =
match model#easy_selection () with
| [sel] when is_uri sel -> sel (* absolute URI selected *)
(* | [sel] -> win#browserUri#entry#text ^ sel |+ relative URI selected +| *)
| [sel] -> lastDir ^ sel
| _ -> assert false
(** history RATIONALE
*
* All operations about history are done using _historyFoo.
* Only toplevel functions (ATM load and loadInput) call _historyAdd.
*)
method private _historyAdd item =
history#add item;
win#browserBackButton#misc#set_sensitive true;
win#browserForwardButton#misc#set_sensitive false
method private _historyPrev () =
let item = history#previous in
if history#is_begin then win#browserBackButton#misc#set_sensitive false;
win#browserForwardButton#misc#set_sensitive true;
item
method private _historyNext () =
let item = history#next in
if history#is_end then win#browserForwardButton#misc#set_sensitive false;
win#browserBackButton#misc#set_sensitive true;
item
(** notebook RATIONALE
*
* Use only these functions to switch between the tabs
*)
method private _showMath = win#mathOrListNotebook#goto_page 0
method private _showList = win#mathOrListNotebook#goto_page 1
method private _showEgg = win#mathOrListNotebook#goto_page 2
method private _showGviz = win#mathOrListNotebook#goto_page 3
method private _showSearch = win#mathOrListNotebook#goto_page 4
method private back () =
try
self#_load (self#_historyPrev ())
with MatitaMisc.History_failure -> ()
method private forward () =
try
self#_load (self#_historyNext ())
with MatitaMisc.History_failure -> ()
(* loads a uri which can be a cic uri or an about:* uri
* @param uri string *)
method private _load ?(force=false) entry =
handle_error (fun () ->
if entry <> current_entry || entry = `About `Current_proof || entry =
`About `Coercions || entry = `About `CoercionsFull || force then
begin
(match entry with
| `About `Current_proof -> self#home ()
| `About `Blank -> self#blank ()
| `About `Us -> self#egg ()
| `About `CoercionsFull -> self#coerchgraph false ()
| `About `Coercions -> self#coerchgraph true ()
| `About `Hints -> self#hints ()
| `About `TeX -> self#tex ()
| `About `Grammar -> self#grammar ()
| `Check term -> self#_loadCheck term
| `NCic (term, ctx, metasenv, subst) ->
self#_loadTermNCic term metasenv subst ctx
| `Dir dir -> self#_loadDir dir
| `NRef nref -> self#_loadNReference nref);
self#setEntry entry
end)
method private blank () =
self#_showMath;
mathView#load_root (Lazy.force empty_mathml)
method private _loadCheck term =
failwith "not implemented _loadCheck";
(* self#_showMath *)
method private egg () =
self#_showEgg;
Lazy.force load_easter_egg
method private redraw_gviz ?center_on () =
if Sys.command "which dot" = 0 then
let tmpfile, oc = Filename.open_temp_file "matita" ".dot" in
let fmt = Format.formatter_of_out_channel oc in
(* MATITA 1.0 MetadataDeps.DepGraph.render fmt gviz_graph;*)
close_out oc;
gviz#load_graph_from_file ~gviz_cmd:"tred | dot" tmpfile;
(match center_on with
| None -> ()
| Some uri -> gviz#center_on_href (NReference.string_of_reference uri));
HExtlib.safe_remove tmpfile
else
MatitaGtkMisc.report_error ~title:"graphviz error"
~message:("Graphviz is not installed but is necessary to render "^
"the graph of dependencies amoung objects. Please install it.")
~parent:win#toplevel ()
method private dependencies direction uri () =
assert false (* MATITA 1.0
let dbd = LibraryDb.instance () in
let graph =
match direction with
| `Fwd -> MetadataDeps.DepGraph.direct_deps ~dbd uri
| `Back -> MetadataDeps.DepGraph.inverse_deps ~dbd uri in
gviz_graph <- graph; (** XXX check this for memory consuption *)
self#redraw_gviz ~center_on:uri ();
self#_showGviz *)
method private coerchgraph tred () =
load_coerchgraph tred ();
self#_showGviz
method private hints () =
load_hints ();
self#_showGviz
method private tex () =
let b = Buffer.create 1000 in
Printf.bprintf b "UTF-8 equivalence classes (rotate with ALT-L):\n\n";
List.iter
(fun l ->
List.iter (fun sym ->
Printf.bprintf b " %s" (Glib.Utf8.from_unichar sym)
) l;
Printf.bprintf b "\n";
)
(List.sort
(fun l1 l2 -> compare (List.hd l1) (List.hd l2))
(Virtuals.get_all_eqclass ()));
Printf.bprintf b "\n\nVirtual keys (trigger with ALT-L):\n\n";
List.iter
(fun tag, items ->
Printf.bprintf b " %s:\n" tag;
List.iter
(fun names, symbol ->
Printf.bprintf b " \t%s\t%s\n"
(Glib.Utf8.from_unichar symbol)
(String.concat ", " names))
(List.sort
(fun (_,a) (_,b) -> compare a b)
items);
Printf.bprintf b "\n")
(List.sort
(fun (a,_) (b,_) -> compare a b)
(Virtuals.get_all_virtuals ()));
self#_loadText (Buffer.contents b)
method private _loadText text =
searchText#source_buffer#set_text text;
win#entrySearch#misc#grab_focus ();
self#_showSearch
method private grammar () =
self#_loadText
(Print_grammar.ebnf_of_term (get_matita_script_current ())#status);
method private home () =
self#_showMath;
let status = (get_matita_script_current ())#status in
match status#ng_mode with
`ProofMode -> self#_loadNObj status status#obj
| _ -> self#blank ()
method private _loadNReference (NReference.Ref (uri,_)) =
let status = (get_matita_script_current ())#status in
let obj = NCicEnvironment.get_checked_obj status uri in
self#_loadNObj status obj
method private _loadDir dir =
let content = Http_getter.ls ~local:false dir in
let l =
List.fast_sort
Pervasives.compare
(List.map
(function
| Http_getter_types.Ls_section s -> "dir", s
| Http_getter_types.Ls_object o -> "obj", o.Http_getter_types.uri)
content)
in
lastDir <- dir;
self#_loadList l
method private setEntry entry =
win#browserUri#set_text (MatitaTypes.string_of_entry entry);
current_entry <- entry
method private _loadNObj status obj =
(* showMath must be done _before_ loading the document, since if the
* widget is not mapped (hidden by the notebook) the document is not
* rendered *)
self#_showMath;
mathView#load_nobject status obj
method private _loadTermNCic term m s c =
let d = 0 in
let m = (0,([],c,term))::m in
let status = (get_matita_script_current ())#status in
mathView#nload_sequent status m s d;
self#_showMath
method private _loadList l =
model#list_store#clear ();
List.iter (fun (tag, s) -> model#easy_append ~tag s) l;
self#_showList
(** { public methods, all must call _load!! } *)
method load entry =
handle_error (fun () -> self#_load entry; self#_historyAdd entry)
(** this is what the browser does when you enter a string an hit enter *)
method loadInput txt =
let txt = HExtlib.trim_blanks txt in
(* (* ZACK: what the heck? *)
let fix_uri txt =
UriManager.string_of_uri
(UriManager.strip_xpointer (UriManager.uri_of_string txt))
in
*)
let entry =
match txt with
| txt when is_uri txt ->
`NRef (NReference.reference_of_string ((*fix_uri*) txt))
| txt when is_dir txt -> `Dir (MatitaMisc.normalize_dir txt)
| txt ->
(try
MatitaTypes.entry_of_string txt
with Invalid_argument _ ->
raise
(GrafiteTypes.Command_error(sprintf "unsupported uri: %s" txt)))
in
self#_load entry;
self#_historyAdd entry
(** {2 methods used by constructor only} *)
method win = win
method history = history
method currentEntry = current_entry
method refresh ~force () = self#_load ~force current_entry
end
let sequentsViewer ~(notebook:GPack.notebook) ~(cicMathView:cicMathView) ():
MatitaGuiTypes.sequentsViewer
=
(new sequentsViewer ~notebook ~cicMathView ():> MatitaGuiTypes.sequentsViewer)
let new_cicBrowser () =
let size = BuildTimeConf.browser_history_size in
let rec aux history =
let browser = new cicBrowser_impl ~history () in
let win = browser#win in
ignore (win#browserNewButton#connect#clicked (fun () ->
let history =
new MatitaMisc.browser_history ~memento:history#save size
(`About `Blank)
in
let newBrowser = aux history in
newBrowser#load browser#currentEntry));
(*
(* attempt (failed) to close windows on CTRL-W ... *)
MatitaGtkMisc.connect_key win#browserWinEventBox#event ~modifiers:[`CONTROL]
GdkKeysyms._W (fun () -> win#toplevel#destroy ());
*)
cicBrowsers := browser :: !cicBrowsers;
browser
in
let history = new MatitaMisc.browser_history size (`About `Blank) in
aux history
(** @param reuse if set reused last opened cic browser otherwise
* opens a new one. default is false *)
let cicBrowser ?(reuse=false) t =
let browser =
if reuse then
(match !cicBrowsers with [] -> new_cicBrowser () | b :: _ -> b)
else
new_cicBrowser ()
in
match t with
None -> ()
| Some t -> browser#load t
;;
let default_cicMathView () =
let res = cicMathView ~show:true () in
res#set_href_callback
(Some (fun uri ->
let uri = `NRef (NReference.reference_of_string uri) in
cicBrowser (Some uri)));
res
let cicMathView_instance =
MatitaMisc.singleton default_cicMathView
let default_sequentsViewer notebook =
let cicMathView = cicMathView_instance () in
sequentsViewer ~notebook ~cicMathView ()
let sequentsViewer_instance =
let already_used = ref false in
fun notebook ->
if !already_used then assert false
else
(already_used := true;
default_sequentsViewer notebook)
let refresh_all_browsers () =
List.iter (fun b -> b#refresh ~force:false ()) !cicBrowsers
let get_math_views () =
(cicMathView_instance ()) :: (List.map (fun b -> b#mathView) !cicBrowsers)
let find_selection_owner () =
let rec aux =
function
| [] -> raise Not_found
| mv :: tl ->
(match mv#get_selections with
| [] -> aux tl
| sel :: _ -> mv)
in
aux (get_math_views ())
let has_selection () =
try ignore (find_selection_owner ()); true
with Not_found -> false
let math_view_clipboard = ref None (* associative list target -> string *)
let has_clipboard () = !math_view_clipboard <> None
let empty_clipboard () = math_view_clipboard := None
let copy_selection () =
try
math_view_clipboard :=
Some ((find_selection_owner ())#strings_of_selection)
with Not_found -> failwith "no selection"
let paste_clipboard paste_kind =
match !math_view_clipboard with
| None -> failwith "empty clipboard"
| Some cb ->
(try List.assoc paste_kind cb with Not_found -> assert false)