________________________________________________________________________

This file is part of Logtalk <https://logtalk.org/>  
Copyright 1998-2019 Paulo Moura <pmoura@logtalk.org>

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 example:

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


% some queries using the list parametric object:

| ?- [1, 2, 3]::member(X).

X = 1 ;
X = 2 ;
X = 3 ;
no

| ?- [1, 2, 3]::last(X).

X = 3
yes

| ?- [1, 2, 3]::nextto(2, Y).

Y = 3
yes

| ?- []::member(X).

no


% some queries using the time and date parametric objects:

| ?- date(Year, Month, Day)::today.

Year = 2000
Month = 8
Day = 15 
yes


| ?- date(Year, _, _)::today, \+ date(Year, _, _)::leap_year.

Year = 2002
yes


| ?- time(Hours, Mins, Secs)::now.

Hours = 13
Mins = 52
Secs = 42 
yes


| ?- rectangle(W, H, X, Y)::init, rectangle(W, H, X, Y)::move(3, 4, NR), NR::position(X2, Y2).

W = 2
H = 1
X = 0
Y = 0
NR = rectangle(2, 1, 3, 4)
X2 = 3
Y2 = 4
yes


% some queries with parametric objects that define "setter"
% methods that return updated object identifiers:

| ?- person(sally, 20)::grow_older(NewId).

NewId = person(sally, 21) 
yes


| ?- employee(sally, 21, 1200)::give_raise(250, NewId).

NewId = employee(sally, 21, 1450) 
yes


% some queries with parametric categories:

| ?- speech(winter, wedding)::advice.

Clothes: [pants, sleeves, heavy]
Speech:  [happy, jokes]
yes
