/* Part of SWI-Prolog
Author: Jan Wielemaker
E-mail: J.Wielemaker@vu.nl
WWW: http://www.swi-prolog.org
Copyright (c) 1999-2019, University of Amsterdam
VU University Amsterdam
CWI, Amsterdam
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the
distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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*/
:- module(edinburgh,
[ display/1,
display/2,
unknown/2,
reconsult/1,
debug/0,
nodebug/0,
fileerrors/2
]).
:- meta_predicate
unknown(:, :),
reconsult(:).
/** <module> Some traditional Edinburgh predicates
This module defines predicates from `traditional Edinburgh Prolog'
(Dec10 and C-Prolog) whose functionality has been replaced by (ISO)
Standard Prolog.
*/
/*******************************
* TERM I/O *
*******************************/
%! display(+Term) is det.
%! display(+Stream, +Term) is det.
%
% Write a term, ignoring operators and special syntax constructs such
% as _brace terms_ (`{a}`) and lists (`[a,b,c]`). Currently does print
% dicts using the dict notation.
%
% @see write_canonical/2. SWI-Prolog's write_canonical/2, however,
% prints lists using lst notation to reduce incompatibility due to the
% modified list functor (`'[|]'` rather than `.`) and reduce memory
% usage while parsing lists.
display(Term) :-
display(current_output, Term).
display(Stream, Term) :-
write_term(Stream, Term,
[ quoted(true),
ignore_ops(true),
no_lists(true),
brace_terms(true)
]).
%! unknown(-Old, +New) is det.
%
% Edinburgh Prolog predicate for dealing dealing with undefined
% procedures
unknown(M:Old, M:New) :-
current_prolog_flag(M:unknown, O),
map_unknown(O, Old),
map_unknown(N, New),
!,
set_prolog_flag(M:unknown, N).
map_unknown(error, trace).
map_unknown(warning, trace).
map_unknown(fail, fail).
%! reconsult(+FileOrList) is det.
%
% Load source file(s), wiping the old content first. SWI-Prolog's
% consult/1 and related predicates always do this.
%
% @deprecated The Edinburgh Prolog consult/reconsult distinction
% is no longer used throughout most of the Prolog world.
reconsult(File) :-
consult(File).
%! debug is det.
%! nodebug is det.
%
% Switch on/off debug mode. Note that nodebug/0 has been defined
% such that is is not traced itself.
debug :- set_prolog_flag(debug, true).
nodebug :- notrace, set_prolog_flag(debug, false).
:- '$hide'(nodebug/0).
%! fileerrors(-Old, +New) is det.
%
% Query and change the fileerrors flag. Default it is set to
% =true=, causing file operations to raise an exception. Setting
% it to =false= activates the old Edinburgh mode of silent
% failure.
%
% @deprecated New code should use catch/3 to handle file errors
% silently
fileerrors(Old, New) :-
current_prolog_flag(fileerrors, Old),
( Old == New
-> true
; set_prolog_flag(fileerrors, New)
).