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, VU University Amsterdam 7 CWI Amsterdam 8 All rights reserved. 9 10 Redistribution and use in source and binary forms, with or without 11 modification, are permitted provided that the following conditions 12 are met: 13 14 1. Redistributions of source code must retain the above copyright 15 notice, this list of conditions and the following disclaimer. 16 17 2. Redistributions in binary form must reproduce the above copyright 18 notice, this list of conditions and the following disclaimer in 19 the documentation and/or other materials provided with the 20 distribution. 21 22 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 23 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 24 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 25 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 26 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 27 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 28 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 29 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 30 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 32 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33 POSSIBILITY OF SUCH DAMAGE. 34*/ 35 36:- module(editline, 37 [ el_wrap/0, % wrap user_input, etc. 38 el_wrap/4, % +Prog, +Input, +Output, +Error 39 el_wrapped/1, % +Input 40 el_unwrap/1, % +Input 41 42 el_source/2, % +Input, +File 43 el_bind/2, % +Input, +Args 44 el_addfn/4, % +Input, +Name, +Help, :Goal 45 el_cursor/2, % +Input, +Move 46 el_line/2, % +Input, -Line 47 el_insertstr/2, % +Input, +Text 48 el_deletestr/2, % +Input, +Count 49 50 el_history/2, % +Input, ?Action 51 el_history_events/2, % +Input, -Events 52 el_add_history/2, % +Input, +Line 53 el_write_history/2, % +Input, +FileName 54 el_read_history/2 % +Input, +FileName 55 ]). 56:- use_module(library(console_input)). 57:- use_module(library(apply)). 58:- use_module(library(lists)). 59 60editline_ok :- 61 \+ current_prolog_flag(console_menu_version, qt), 62 \+ current_prolog_flag(readline, readline), 63 stream_property(user_input, tty(true)). 64 65:- use_foreign_library(foreign(libedit4pl)). 66 67:- if(editline_ok). 68:- initialization el_wrap. 69:- endif. 70 71:- meta_predicate 72 el_addfn(,,,). 73 74:- multifile 75 el_setup/1. % +Input
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).
97el_wrap :- 98 el_wrapped(user_input), 99 !. 100el_wrap :- 101 stream_property(user_input, tty(true)), !, 102 el_wrap(swipl, user_input, user_output, user_error), 103 add_prolog_commands(user_input), 104 forall(el_setup(user_input), true). 105el_wrap. 106 107add_prolog_commands(Input) :- 108 el_addfn(Input, complete, 'Complete atoms and files', complete), 109 el_addfn(Input, show_completions, 'List completions', show_completions), 110 el_addfn(Input, electric, 'Indicate matching bracket', electric), 111 el_bind(Input, ["^I", complete]), 112 el_bind(Input, ["^[?", show_completions]), 113 bind_electric(Input), 114 el_source(Input, _).
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.$HOME/.editrcbind command with the given arguments. The
example below lists the current key bindings.
?- el_bind(user_input, ['-a']).
The predicate el_bind/2 is typically used to bind commands defined using el_addfn/4. Note that the C proxy function has only the last character of the command as context to find the Prolog binding. This implies we cannot both bind e.g., "^[?" *and "?" to a Prolog function.
bind -a (see el_bind/2) and Goal is called of the
associated key-binding is activated. Goal is called as
call(:Goal, +Input, +Char, -Continue)
where Input is the input stream providing access to the editor, Char
the activating character and Continue must be instantated with one
of the known continuation codes as defined by libedit: norm,
newline, eof, arghack, refresh, refresh_beep, cursor,
redisplay, error or fatal. In addition, the following Continue
code is provided.
The registered Goal typically used el_line/2 to fetch the input line and el_cursor/2, el_insertstr/2 and/or el_deletestr/2 to manipulate the input line.
Normally el_bind/2 is used to associate the defined command with a keyboard sequence.
line(Before,
After), where Before is a string holding the text before the
cursor and After is a string holding the text after the cursor.history() from libedit. Supported actions are:
Num-String, where
Num is the event number and String is the associated string
without terminating newline.252:- multifile 253 prolog:history/2. 254 255prologhistory(Input, add(Line)) :- 256 el_add_history(Input, Line). 257prologhistory(Input, load(File)) :- 258 el_read_history(Input, File). 259prologhistory(Input, save(File)) :- 260 el_write_history(Input, File). 261prologhistory(Input, load) :- 262 el_history_events(Input, Events), 263 '$reverse'(Events, RevEvents), 264 forall('$member'(Ev, RevEvents), 265 add_event(Ev)). 266 267add_event(Num-String) :- 268 remove_dot(String, String1), 269 '$save_history_event'(Num-String1). 270 271remove_dot(String0, String) :- 272 string_concat(String, ".", String0), 273 !. 274remove_dot(String, String). 275 276 277 /******************************* 278 * ELECTRIC CARET * 279 *******************************/
285bind_electric(Input) :- 286 forall(bracket(_Open, Close), bind_code(Input, Close, electric)), 287 forall(quote(Close), bind_code(Input, Close, electric)). 288 289bind_code(Input, Code, Command) :- 290 string_codes(Key, [Code]), 291 el_bind(Input, [Key, Command]).
296electric(Input, Char, Continue) :- 297 string_codes(Str, [Char]), 298 el_insertstr(Input, Str), 299 el_line(Input, line(Before, _)), 300 ( string_codes(Before, Codes), 301 nesting(Codes, 0, Nesting), 302 reverse(Nesting, [Close|RevNesting]) 303 -> ( Close = open(_,_) % open quote 304 -> Continue = refresh 305 ; matching_open(RevNesting, Close, _, Index) 306 -> string_length(Before, Len), % Proper match 307 Move is Index-Len, 308 Continue = electric(Move, 500, refresh) 309 ; Continue = refresh_beep % Not properly nested 310 ) 311 ; Continue = refresh_beep 312 ). 313 314matching_open_index(String, Index) :- 315 string_codes(String, Codes), 316 nesting(Codes, 0, Nesting), 317 reverse(Nesting, [Close|RevNesting]), 318 matching_open(RevNesting, Close, _, Index). 319 320matching_open([Open|Rest], Close, Rest, Index) :- 321 Open = open(Index,_), 322 match(Open, Close), 323 !. 324matching_open([Close1|Rest1], Close, Rest, Index) :- 325 Close1 = close(_,_), 326 matching_open(Rest1, Close1, Rest2, _), 327 matching_open(Rest2, Close, Rest, Index). 328 329match(open(_,Open),close(_,Close)) :- 330 ( bracket(Open, Close) 331 -> true 332 ; Open == Close, 333 quote(Open) 334 ). 335 336bracket(0'(, 0')). 337bracket(0'[, 0']). 338bracket(0'{, 0'}). 339 340quote(0'\'). 341quote(0'\"). 342quote(0'\`). 343 344nesting([], _, []). 345nesting([H|T], I, Nesting) :- 346 ( bracket(H, _Close) 347 -> Nesting = [open(I,H)|Nest] 348 ; bracket(_Open, H) 349 -> Nesting = [close(I,H)|Nest] 350 ), 351 !, 352 I2 is I+1, 353 nesting(T, I2, Nest). 354nesting([0'0, 0'\'|T], I, Nesting) :- 355 !, 356 phrase(skip_code, T, T1), 357 difflist_length(T, T1, Len), 358 I2 is I+Len+2, 359 nesting(T1, I2, Nesting). 360nesting([H|T], I, Nesting) :- 361 quote(H), 362 !, 363 ( phrase(skip_quoted(H), T, T1) 364 -> difflist_length(T, T1, Len), 365 I2 is I+Len+1, 366 Nesting = [open(I,H),close(I2,H)|Nest], 367 nesting(T1, I2, Nest) 368 ; Nesting = [open(I,H)] % Open quote 369 ). 370nesting([_|T], I, Nesting) :- 371 I2 is I+1, 372 nesting(T, I2, Nesting). 373 374difflist_length(List, Tail, Len) :- 375 difflist_length(List, Tail, 0, Len). 376 377difflist_length(List, Tail, Len0, Len) :- 378 List == Tail, 379 !, 380 Len = Len0. 381difflist_length([_|List], Tail, Len0, Len) :- 382 Len1 is Len0+1, 383 difflist_length(List, Tail, Len1, Len). 384 385skip_quoted(H) --> 386 [H], 387 !. 388skip_quoted(H) --> 389 "\\", [H], 390 !, 391 skip_quoted(H). 392skip_quoted(H) --> 393 [_], 394 skip_quoted(H). 395 396skip_code --> 397 "\\", [_], 398 !. 399skip_code --> 400 [_]. 401 402 403 /******************************* 404 * COMPLETION * 405 *******************************/
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.416:- dynamic 417 last_complete/2. 418 419complete(Input, _Char, Continue) :- 420 el_line(Input, line(Before, After)), 421 prolog:complete_input(Before, After, Delete, Completions), 422 ( Completions = [One] 423 -> string_length(Delete, Len), 424 el_deletestr(Input, Len), 425 complete_text(One, Text), 426 el_insertstr(Input, Text), 427 Continue = refresh 428 ; Completions == [] 429 -> Continue = refresh_beep 430 ; get_time(Now), 431 retract(last_complete(TLast, Before)), 432 Now - TLast < 2 433 -> nl(user_error), 434 list_alternatives(Completions), 435 Continue = redisplay 436 ; retractall(last_complete(_,_)), 437 get_time(Now), 438 asserta(last_complete(Now, Before)), 439 common_competion(Completions, Extend), 440 ( Delete == Extend 441 -> Continue = refresh_beep 442 ; string_length(Delete, Len), 443 el_deletestr(Input, Len), 444 el_insertstr(Input, Extend), 445 Continue = refresh 446 ) 447 ).
453show_completions(Input, _Char, Continue) :- 454 el_line(Input, line(Before, After)), 455 prolog:complete_input(Before, After, _Delete, Completions), 456 nl(user_error), 457 list_alternatives(Completions), 458 Continue = redisplay. 459 460complete_text(Text-_Comment, Text) :- !. 461complete_text(Text, Text).
467common_competion(Alternatives, Common) :- 468 maplist(atomic, Alternatives), 469 !, 470 common_prefix(Alternatives, Common). 471common_competion(Alternatives, Common) :- 472 maplist(complete_text, Alternatives, AltText), 473 !, 474 common_prefix(AltText, Common).
480common_prefix([A1|T], Common) :- 481 common_prefix_(T, A1, Common). 482 483common_prefix_([], Common, Common). 484common_prefix_([H|T], Common0, Common) :- 485 common_prefix(H, Common0, Common1), 486 common_prefix_(T, Common1, Common).
492common_prefix(A1, A2, Prefix) :- 493 sub_atom(A1, 0, _, _, A2), 494 !, 495 Prefix = A2. 496common_prefix(A1, A2, Prefix) :- 497 sub_atom(A2, 0, _, _, A1), 498 !, 499 Prefix = A1. 500common_prefix(A1, A2, Prefix) :- 501 atom_codes(A1, C1), 502 atom_codes(A2, C2), 503 list_common_prefix(C1, C2, C), 504 string_codes(Prefix, C). 505 506list_common_prefix([H|T0], [H|T1], [H|T]) :- 507 !, 508 list_common_prefix(T0, T1, T). 509list_common_prefix(_, _, []).
519list_alternatives(Alternatives) :- 520 maplist(atomic, Alternatives), 521 !, 522 length(Alternatives, Count), 523 maplist(atom_length, Alternatives, Lengths), 524 max_list(Lengths, Max), 525 tty_size(_, Cols), 526 ColW is Max+2, 527 Columns is max(1, Cols // ColW), 528 RowCount is (Count+Columns-1)//Columns, 529 length(Rows, RowCount), 530 to_matrix(Alternatives, Rows, Rows), 531 ( RowCount > 11 532 -> length(First, 10), 533 Skipped is RowCount - 10, 534 append(First, _, Rows), 535 maplist(write_row(ColW), First), 536 format(user_error, '... skipped ~D rows~n', [Skipped]) 537 ; maplist(write_row(ColW), Rows) 538 ). 539list_alternatives(Alternatives) :- 540 maplist(complete_text, Alternatives, AltText), 541 list_alternatives(AltText). 542 543to_matrix([], _, Rows) :- 544 !, 545 maplist(close_list, Rows). 546to_matrix([H|T], [RH|RT], Rows) :- 547 !, 548 add_list(RH, H), 549 to_matrix(T, RT, Rows). 550to_matrix(List, [], Rows) :- 551 to_matrix(List, Rows, Rows). 552 553add_list(Var, Elem) :- 554 var(Var), !, 555 Var = [Elem|_]. 556add_list([_|T], Elem) :- 557 add_list(T, Elem). 558 559close_list(List) :- 560 append(List, [], _), 561 !. 562 563write_row(ColW, Row) :- 564 length(Row, Columns), 565 make_format(Columns, ColW, Format), 566 format(user_error, Format, Row). 567 568make_format(N, ColW, Format) :- 569 format(string(PerCol), '~~w~~t~~~d+', [ColW]), 570 Front is N - 1, 571 length(LF, Front), 572 maplist(=(PerCol), LF), 573 append(LF, ['~w~n'], Parts), 574 atomics_to_string(Parts, Format)
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. */