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This file is part of Logtalk https://logtalk.org/ SPDX-FileCopyrightText: 1998-2023 Paulo Moura <pmoura@logtalk.org> SPDX-License-Identifier: Apache-2.0

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

% start by loading the loading the example:

| ?- logtalk_load(sync(loader)). ...

% slow print text

| ?- slow_print::start. abc 123 abc 123 abc 123 abc 123 abc ...

% send three asynchronous messages whose corresponding methods perform output operations:

| ?- threaded_ignore(nasty1::io(alpha)), threaded_ignore(nasty1::io(digit)), threaded_ignore(nasty1::io(alpha)).

a0ab1bc2c3ddefef45gg6hh7ii8jkjk9 llmmnnopopqqrrsstztzyyxxwwuv uv

Yes

% send three asynchronous messages whose corresponding methods perform database updates % (this may or may not work, most likely will throw an exception):

| ?- threaded_ignore(nasty1::update_db(_)), threaded_ignore(nasty1::update_db(_)), threaded_ignore(nasty1::update_db(_)).

No

% the best solution is to declare predicates that need to be thread synchronized as "synchronized", % as exemplified in object "nasty2":

| ?- threaded_ignore(nasty2::io(alpha)), threaded_ignore(nasty2::io(digit)), threaded_ignore(nasty2::io(alpha)).

abcdefghijklmnopqrstzyxwuv 0123456789 abcdefghijklmnopqrstzyxwuv

Yes

| ?- threaded_call(nasty2::update_db(_)), threaded_call(nasty2::update_db(_)), threaded_call(nasty2::update_db(_)).

Yes

| ?- threaded_exit(nasty2::update_db(X)), threaded_exit(nasty2::update_db(Y)), threaded_exit(nasty2::update_db(Z)).

X = 1 Y = 2 Z = 3

Yes