1/* Part of SWI-Prolog 2 3 Author: Jan Wielemaker 4 E-mail: J.Wielemaker@vu.nl 5 WWW: http://www.swi-prolog.org 6 Copyright (c) 2017-2025, VU University Amsterdam 7 CWI Amsterdam 8 SWI-Prolog Solutions b.v. 9 All rights reserved. 10 11 Redistribution and use in source and binary forms, with or without 12 modification, are permitted provided that the following conditions 13 are met: 14 15 1. Redistributions of source code must retain the above copyright 16 notice, this list of conditions and the following disclaimer. 17 18 2. Redistributions in binary form must reproduce the above copyright 19 notice, this list of conditions and the following disclaimer in 20 the documentation and/or other materials provided with the 21 distribution. 22 23 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 26 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 27 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 28 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 29 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 30 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 31 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 33 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 POSSIBILITY OF SUCH DAMAGE. 35*/ 36 37:- module(editline, 38 [ el_wrap/0, % wrap user_input, etc. 39 el_wrap/1, % +Options 40 el_wrap/4, % +Prog, +Input, +Output, +Error 41 el_wrap/5, % +Prog, +Input, +Output, +Error, +Options 42 el_wrapped/1, % +Input 43 el_unwrap/1, % +Input 44 45 el_source/2, % +Input, +File 46 el_bind/2, % +Input, +Args 47 el_addfn/4, % +Input, +Name, +Help, :Goal 48 el_cursor/2, % +Input, +Move 49 el_line/2, % +Input, -Line 50 el_insertstr/2, % +Input, +Text 51 el_deletestr/2, % +Input, +Count 52 53 el_history/2, % +Input, ?Action 54 el_history_events/2, % +Input, -Events 55 el_add_history/2, % +Input, +Line 56 el_write_history/2, % +Input, +FileName 57 el_read_history/2 % +Input, +FileName 58 ]). 59:- autoload(library(apply),[maplist/2,maplist/3]). 60:- autoload(library(lists),[reverse/2,max_list/2,append/3,member/2]). 61:- autoload(library(solution_sequences),[call_nth/2]). 62 63:- use_foreign_library(foreign(libedit4pl)). 64 65:- initialization el_wrap_if_ok. 66 67:- meta_predicate 68 el_addfn(,,,). 69 70:- multifile 71 el_setup/1, % +Input 72 prolog:complete_input/4.
83el_wrap_if_ok :- 84 \+ current_prolog_flag(console_menu_version, qt), 85 \+ current_prolog_flag(readline, readline), 86 stream_property(user_input, tty(true)), 87 !, 88 el_wrap. 89el_wrap_if_ok.
user_input
is connected to a terminal. This is the high level predicate used
for most purposes. The remainder of the library interface deals with
low level predicates that allows for applying and programming
libedit in non-standard situations.
The library is registered with ProgName set to swipl (see
el_wrap/4).
103el_wrap :- 104 el_wrap([]). 105 106el_wrap(_) :- 107 el_wrapped(user_input), 108 !. 109el_wrap(Options) :- 110 stream_property(user_input, tty(true)), !, 111 el_wrap(swipl, user_input, user_output, user_error, Options), 112 add_prolog_commands(user_input), 113 forall(el_setup(user_input), true). 114el_wrap(_). 115 116add_prolog_commands(Input) :- 117 el_addfn(Input, complete, 'Complete atoms and files', complete), 118 el_addfn(Input, show_completions, 'List completions', show_completions), 119 el_addfn(Input, electric, 'Indicate matching bracket', electric), 120 el_addfn(Input, isearch_history, 'Incremental search in history', 121 isearch_history), 122 el_bind(Input, ["^I", complete]), 123 el_bind(Input, ["^[?", show_completions]), 124 el_bind(Input, ["^R", isearch_history]), 125 bind_electric(Input), 126 add_paste_quoted(Input), 127 el_source(Input, _).
142el_wrap(ProgName, In, Out, Error) :-
143 el_wrap(ProgName, In, Out, Error, []).forall(el_setup(Input), true) after the
input stream has been wrapped, the default Prolog commands have been
added and the default user setup file has been sourced using
el_source/2. It can be used to define and bind additional commands.$HOME/.editrcbind command with the given arguments. The
example below lists the current key bindings.
?- el_bind(user_input, ['-a']).
The predicate el_bind/2 is typically used to bind commands defined using el_addfn/4. Note that the C proxy function has only the last character of the command as context to find the Prolog binding. This implies we cannot both bind e.g., "^[?" *and "?" to a Prolog function.
bind -a (see el_bind/2) and Goal is called of the
associated key-binding is activated. Goal is called as
call(:Goal, +Input, +Char, -Continue)
where Input is the input stream providing access to the editor, Char
the activating character and Continue must be instantated with one
of the known continuation codes as defined by libedit: norm,
newline, eof, arghack, refresh, refresh_beep, cursor,
redisplay, error or fatal. In addition, the following Continue
code is provided.
The registered Goal typically used el_line/2 to fetch the input line and el_cursor/2, el_insertstr/2 and/or el_deletestr/2 to manipulate the input line.
Normally el_bind/2 is used to associate the defined command with a keyboard sequence.
line(Before,
After), where Before is a string holding the text before the
cursor and After is a string holding the text after the cursor.history() from libedit. Supported actions are:
Num-String, where
Num is the event number and String is the associated string
without terminating newline.273:- multifile 274 prolog:history/2. 275 276prologhistory(Input, add(Line)) :- 277 el_add_history(Input, Line). 278prologhistory(Input, load(File)) :- 279 el_read_history(Input, File). 280prologhistory(Input, save(File)) :- 281 el_write_history(Input, File). 282prologhistory(Input, load) :- 283 el_history_events(Input, Events), 284 load_history_events(Events).
boot/history.pl290load_history_events(Events) :- 291 '$reverse'(Events, RevEvents), 292 forall('$member'(Ev, RevEvents), 293 add_event(Ev)). 294 295add_event(Num-String) :- 296 remove_dot(String, String1), 297 '$save_history_event'(Num-String1). 298 299remove_dot(String0, String) :- 300 string_concat(String, ".", String0), 301 !. 302remove_dot(String, String). 303 304 305 /******************************* 306 * ELECTRIC CARET * 307 *******************************/
313bind_electric(Input) :- 314 forall(bracket(_Open, Close), bind_code(Input, Close, electric)), 315 forall(quote(Close), bind_code(Input, Close, electric)). 316 317bind_code(Input, Code, Command) :- 318 string_codes(Key, [Code]), 319 el_bind(Input, [Key, Command]).
324electric(Input, Char, Continue) :- 325 string_codes(Str, [Char]), 326 el_insertstr(Input, Str), 327 el_line(Input, line(Before, _)), 328 ( string_codes(Before, Codes), 329 nesting(Codes, 0, Nesting), 330 reverse(Nesting, [Close|RevNesting]) 331 -> ( Close = open(_,_) % open quote 332 -> Continue = refresh 333 ; matching_open(RevNesting, Close, _, Index) 334 -> string_length(Before, Len), % Proper match 335 Move is Index-Len, 336 Continue = electric(Move, 500, refresh) 337 ; Continue = refresh_beep % Not properly nested 338 ) 339 ; Continue = refresh_beep 340 ). 341 342matching_open_index(String, Index) :- 343 string_codes(String, Codes), 344 nesting(Codes, 0, Nesting), 345 reverse(Nesting, [Close|RevNesting]), 346 matching_open(RevNesting, Close, _, Index). 347 348matching_open([Open|Rest], Close, Rest, Index) :- 349 Open = open(Index,_), 350 match(Open, Close), 351 !. 352matching_open([Close1|Rest1], Close, Rest, Index) :- 353 Close1 = close(_,_), 354 matching_open(Rest1, Close1, Rest2, _), 355 matching_open(Rest2, Close, Rest, Index). 356 357match(open(_,Open),close(_,Close)) :- 358 ( bracket(Open, Close) 359 -> true 360 ; Open == Close, 361 quote(Open) 362 ). 363 364bracket(0'(, 0')). 365bracket(0'[, 0']). 366bracket(0'{, 0'}). 367 368quote(0'\'). 369quote(0'\"). 370quote(0'\`). 371 372nesting([], _, []). 373nesting([H|T], I, Nesting) :- 374 ( bracket(H, _Close) 375 -> Nesting = [open(I,H)|Nest] 376 ; bracket(_Open, H) 377 -> Nesting = [close(I,H)|Nest] 378 ), 379 !, 380 I2 is I+1, 381 nesting(T, I2, Nest). 382nesting([0'0, 0'\'|T], I, Nesting) :- 383 !, 384 phrase(skip_code, T, T1), 385 difflist_length(T, T1, Len), 386 I2 is I+Len+2, 387 nesting(T1, I2, Nesting). 388nesting([H|T], I, Nesting) :- 389 quote(H), 390 !, 391 ( phrase(skip_quoted(H), T, T1) 392 -> difflist_length(T, T1, Len), 393 I2 is I+Len+1, 394 Nesting = [open(I,H),close(I2,H)|Nest], 395 nesting(T1, I2, Nest) 396 ; Nesting = [open(I,H)] % Open quote 397 ). 398nesting([_|T], I, Nesting) :- 399 I2 is I+1, 400 nesting(T, I2, Nesting). 401 402difflist_length(List, Tail, Len) :- 403 difflist_length(List, Tail, 0, Len). 404 405difflist_length(List, Tail, Len0, Len) :- 406 List == Tail, 407 !, 408 Len = Len0. 409difflist_length([_|List], Tail, Len0, Len) :- 410 Len1 is Len0+1, 411 difflist_length(List, Tail, Len1, Len). 412 413skip_quoted(H) --> 414 [H], 415 !. 416skip_quoted(H) --> 417 "\\", [H], 418 !, 419 skip_quoted(H). 420skip_quoted(H) --> 421 [_], 422 skip_quoted(H). 423 424skip_code --> 425 "\\", [_], 426 !. 427skip_code --> 428 [_]. 429 430 431 /******************************* 432 * COMPLETION * 433 *******************************/
complete editline function. The
predicate is called with three arguments, the first being the input
stream used to access the libedit functions and the second the
activating character. The last argument tells libedit what to do.
Consult el_set(3), EL_ADDFN for details.444:- dynamic 445 last_complete/2. 446 447complete(Input, _Char, Continue) :- 448 el_line(Input, line(Before, After)), 449 ensure_input_completion, 450 prolog:complete_input(Before, After, Delete, Completions), 451 ( Completions = [One] 452 -> string_length(Delete, Len), 453 el_deletestr(Input, Len), 454 complete_text(One, Text), 455 el_insertstr(Input, Text), 456 Continue = refresh 457 ; Completions == [] 458 -> Continue = refresh_beep 459 ; get_time(Now), 460 retract(last_complete(TLast, Before)), 461 Now - TLast < 2 462 -> nl(user_error), 463 list_alternatives(Completions), 464 Continue = redisplay 465 ; retractall(last_complete(_,_)), 466 get_time(Now), 467 asserta(last_complete(Now, Before)), 468 common_competion(Completions, Extend), 469 ( Delete == Extend 470 -> Continue = refresh_beep 471 ; string_length(Delete, Len), 472 el_deletestr(Input, Len), 473 el_insertstr(Input, Extend), 474 Continue = refresh 475 ) 476 ). 477 478:- dynamic 479 input_completion_loaded/0. 480 481ensure_input_completion :- 482 input_completion_loaded, 483 !. 484ensure_input_completion :- 485 predicate_property(prolog:complete_input(_,_,_,_), 486 number_of_clauses(N)), 487 N > 0, 488 !. 489ensure_input_completion :- 490 exists_source(library(console_input)), 491 !, 492 use_module(library(console_input), []), 493 asserta(input_completion_loaded). 494ensure_input_completion.
501show_completions(Input, _Char, Continue) :- 502 el_line(Input, line(Before, After)), 503 prolog:complete_input(Before, After, _Delete, Completions), 504 nl(user_error), 505 list_alternatives(Completions), 506 Continue = redisplay. 507 508complete_text(Text-_Comment, Text) :- !. 509complete_text(Text, Text).
515common_competion(Alternatives, Common) :- 516 maplist(atomic, Alternatives), 517 !, 518 common_prefix(Alternatives, Common). 519common_competion(Alternatives, Common) :- 520 maplist(complete_text, Alternatives, AltText), 521 !, 522 common_prefix(AltText, Common).
528common_prefix([A1|T], Common) :- 529 common_prefix_(T, A1, Common). 530 531common_prefix_([], Common, Common). 532common_prefix_([H|T], Common0, Common) :- 533 common_prefix(H, Common0, Common1), 534 common_prefix_(T, Common1, Common).
540common_prefix(A1, A2, Prefix) :- 541 sub_atom(A1, 0, _, _, A2), 542 !, 543 Prefix = A2. 544common_prefix(A1, A2, Prefix) :- 545 sub_atom(A2, 0, _, _, A1), 546 !, 547 Prefix = A1. 548common_prefix(A1, A2, Prefix) :- 549 atom_codes(A1, C1), 550 atom_codes(A2, C2), 551 list_common_prefix(C1, C2, C), 552 string_codes(Prefix, C). 553 554list_common_prefix([H|T0], [H|T1], [H|T]) :- 555 !, 556 list_common_prefix(T0, T1, T). 557list_common_prefix(_, _, []).
567list_alternatives(Alternatives) :- 568 maplist(atomic, Alternatives), 569 !, 570 length(Alternatives, Count), 571 maplist(atom_length, Alternatives, Lengths), 572 max_list(Lengths, Max), 573 tty_size(_, Cols), 574 ColW is Max+2, 575 Columns is max(1, Cols // ColW), 576 RowCount is (Count+Columns-1)//Columns, 577 length(Rows, RowCount), 578 to_matrix(Alternatives, Rows, Rows), 579 ( RowCount > 11 580 -> length(First, 10), 581 Skipped is RowCount - 10, 582 append(First, _, Rows), 583 maplist(write_row(ColW), First), 584 format(user_error, '... skipped ~D rows~n', [Skipped]) 585 ; maplist(write_row(ColW), Rows) 586 ). 587list_alternatives(Alternatives) :- 588 maplist(complete_text, Alternatives, AltText), 589 list_alternatives(AltText). 590 591to_matrix([], _, Rows) :- 592 !, 593 maplist(close_list, Rows). 594to_matrix([H|T], [RH|RT], Rows) :- 595 !, 596 add_list(RH, H), 597 to_matrix(T, RT, Rows). 598to_matrix(List, [], Rows) :- 599 to_matrix(List, Rows, Rows). 600 601add_list(Var, Elem) :- 602 var(Var), !, 603 Var = [Elem|_]. 604add_list([_|T], Elem) :- 605 add_list(T, Elem). 606 607close_list(List) :- 608 append(List, [], _), 609 !. 610 611write_row(ColW, Row) :- 612 length(Row, Columns), 613 make_format(Columns, ColW, Format), 614 format(user_error, Format, Row). 615 616make_format(N, ColW, Format) :- 617 format(string(PerCol), '~~w~~t~~~d+', [ColW]), 618 Front is N - 1, 619 length(LF, Front), 620 maplist(=(PerCol), LF), 621 append(LF, ['~w~n'], Parts), 622 atomics_to_string(Parts, Format). 623 624 625 /******************************* 626 * SEARCH * 627 *******************************/
634isearch_history(Input, _Char, Continue) :- 635 el_line(Input, line(Before, After)), 636 string_concat(Before, After, Current), 637 string_length(Current, Len), 638 search_print('', "", Current), 639 search(Input, "", Current, 1, Line), 640 el_deletestr(Input, Len), 641 el_insertstr(Input, Line), 642 Continue = redisplay. 643 644search(Input, For, Current, Nth, Line) :- 645 el_getc(Input, Next), 646 Next \== -1, 647 !, 648 search(Next, Input, For, Current, Nth, Line). 649search(_Input, _For, _Current, _Nth, ""). 650 651search(7, _Input, _, Current, _, Current) :- % C-g: abort 652 !, 653 clear_line. 654search(18, Input, For, Current, Nth, Line) :- % C-r: search previous 655 !, 656 N2 is Nth+1, 657 search_(Input, For, Current, N2, Line). 658search(19, Input, For, Current, Nth, Line) :- % C-s: search next 659 !, 660 N2 is max(1,Nth-1), 661 search_(Input, For, Current, N2, Line). 662search(127, Input, For, Current, _Nth, Line) :- % DEL/BS: shorten search 663 sub_string(For, 0, _, 1, For1), 664 !, 665 search_(Input, For1, Current, 1, Line). 666search(Char, Input, For, Current, Nth, Line) :- 667 code_type(Char, cntrl), 668 !, 669 search_end(Input, For, Current, Nth, Line), 670 el_push(Input, Char). 671search(Char, Input, For, Current, _Nth, Line) :- 672 format(string(For1), '~w~c', [For,Char]), 673 search_(Input, For1, Current, 1, Line). 674 675search_(Input, For1, Current, Nth, Line) :- 676 ( find_in_history(Input, For1, Current, Nth, Candidate) 677 -> search_print('', For1, Candidate) 678 ; search_print('failed ', For1, Current) 679 ), 680 search(Input, For1, Current, Nth, Line). 681 682search_end(Input, For, Current, Nth, Line) :- 683 ( find_in_history(Input, For, Current, Nth, Line) 684 -> true 685 ; Line = Current 686 ), 687 clear_line. 688 689find_in_history(_, "", Current, _, Current) :- 690 !. 691find_in_history(Input, For, _, Nth, Line) :- 692 el_history_events(Input, History), 693 call_nth(( member(_N-Line, History), 694 sub_string(Line, _, _, _, For) 695 ), 696 Nth), 697 !. 698 699search_print(State, Search, Current) :- 700 format(user_error, '\r(~wreverse-i-search)`~w\': ~w\e[0K', 701 [State, Search, Current]). 702 703clear_line :- 704 format(user_error, '\r\e[0K', []). 705 706 707 /******************************* 708 * PASTE QUOTED * 709 *******************************/ 710 711:- meta_predicate 712 with_quote_flags(,,). 713 714add_paste_quoted(Input) :- 715 current_prolog_flag(gui, true), 716 !, 717 el_addfn(Input, paste_quoted, 'Paste as quoted atom', paste_quoted), 718 el_bind(Input, ["^Y", paste_quoted]). 719add_paste_quoted(_).
727paste_quoted(Input, _Char, Continue) :- 728 clipboard_content(String), 729 quote_text(Input, String, Quoted), 730 el_insertstr(Input, Quoted), 731 Continue = refresh. 732 733quote_text(Input, String, Value) :- 734 el_line(Input, line(Before, _After)), 735 ( sub_string(Before, _, 1, 0, Quote) 736 -> true 737 ; Quote = "'" 738 ), 739 quote_text(Input, Quote, String, Value). 740 741quote_text(Input, "'", Text, Quoted) => 742 format(string(Quoted), '~q', [Text]), 743 el_deletestr(Input, 1). 744quote_text(Input, "\"", Text, Quoted) => 745 atom_string(Text, String), 746 with_quote_flags( 747 string, codes, 748 format(string(Quoted), '~q', [String])), 749 el_deletestr(Input, 1). 750quote_text(Input, "`", Text, Quoted) => 751 atom_string(Text, String), 752 with_quote_flags( 753 codes, string, 754 format(string(Quoted), '~q', [String])), 755 el_deletestr(Input, 1). 756quote_text(_, _, Text, Quoted) => 757 format(string(Quoted), '~q', [Text]). 758 759with_quote_flags(Double, Back, Goal) :- 760 current_prolog_flag(double_quotes, ODouble), 761 current_prolog_flag(back_quotes, OBack), 762 setup_call_cleanup( 763 ( set_prolog_flag(double_quotes, Double), 764 set_prolog_flag(back_quotes, Back) ), 765 Goal, 766 ( set_prolog_flag(double_quotes, ODouble), 767 set_prolog_flag(back_quotes, OBack) )). 768 769clipboard_content(Text) :- 770 current_prolog_flag(gui, true), 771 !, 772 autoload_call(in_pce_thread_sync( 773 autoload_call( 774 get(@(display), paste, primary, string(Text))))). 775clipboard_content("")
BSD libedit based command line editing
This library wraps the BSD libedit command line editor. The binding provides a high level API to enable command line editing on the Prolog user streams and low level predicates to apply the library on other streams and program the library. */