<?php
date_default_timezone_set('Europe/London');
$date3 = DateTime::createFromFormat('Y-m-d H:i:s', '2019-04-01 00:00:00'); // 2019-04-01 00:00:00.0 Europe/London (+01:00)
$date4 = clone $date3;
$date4->modify('+5 week'); // 2019-05-06 00:00:00.0 Europe/London (+01:00)
echo "So the originally modified date with 5 weeks added is:";
print_r($date4);
echo "\n\n";
// positive DIFF and addition
echo "1. positive DIFF and addition\n";
echo "diff is: ";
$positiveDifferenceDateInterval2 = $date3->diff($date4); // interval: + 1m 4d; days 35
print_r($positiveDifferenceDateInterval2->format('%R %mm %dd'));
echo "; days: {$positiveDifferenceDateInterval2->days} \n";
$positiveAddedDate = clone $date3;
$positiveAddedDate->add($positiveDifferenceDateInterval2);
print_r($positiveAddedDate);
echo "is it equal to \$date4? ";
var_dump($date4->getTimestamp() === $positiveAddedDate->getTimestamp());
echo "\n";
// negative DIFF and addition
echo "2. negative DIFF and addition\n";
echo "diff is: ";
$negativeDifferenceDateInterval2 = $date4->diff($date3); // interval: - 1m 5d; days 35
print_r($negativeDifferenceDateInterval2->format('%R %mm %dd'));
echo "; days {$negativeDifferenceDateInterval2->days}";
$negativeAddedDate = clone $date3;
// so in order to make it equal to $date4 I need to subtract a negative interval instead of adding a positive one? how crazy is that?!
$negativeAddedDate->sub($negativeDifferenceDateInterval2);
print_r($negativeAddedDate);
echo "is it equal to \$date4? ";
var_dump($date4->getTimestamp() === $negativeAddedDate->getTimestamp());
echo "\n\n";
echo 'So in order to make it equal to $date4 I need to subtract a negative interval instead of adding a positive one? How crazy is that?!';
So the originally modified date with 5 weeks added is:DateTime Object
(
[date] => 2019-05-06 00:00:00.000000
[timezone_type] => 3
[timezone] => Europe/London
)
1. positive DIFF and addition
diff is: + 1m 5d; days: 35
DateTime Object
(
[date] => 2019-05-06 00:00:00.000000
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(true)
2. negative DIFF and addition
diff is: - 1m 5d; days 35DateTime Object
(
[date] => 2019-05-06 00:00:00.000000
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(true)
So in order to make it equal to $date4 I need to subtract a negative interval instead of adding a positive one? How crazy is that?!
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0
So the originally modified date with 5 weeks added is:DateTime Object
(
[date] => 2019-05-06 00:00:00.000000
[timezone_type] => 3
[timezone] => Europe/London
)
1. positive DIFF and addition
diff is: + 1m 5d; days: 35
DateTime Object
(
[date] => 2019-05-06 00:00:00.000000
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(true)
2. negative DIFF and addition
diff is: - 1m 5d; days 35DateTime Object
(
[date] => 2019-05-06 00:00:00.000000
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(true)
So in order to make it equal to $date4 I need to subtract a negative interval instead of adding a positive one? How crazy is that?!
So the originally modified date with 5 weeks added is:DateTime Object
(
[date] => 2019-05-06 00:00:00.000000
[timezone_type] => 3
[timezone] => Europe/London
)
1. positive DIFF and addition
diff is: + 1m 4d; days: 35
DateTime Object
(
[date] => 2019-05-05 00:00:00.000000
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(false)
2. negative DIFF and addition
diff is: - 1m 5d; days 35DateTime Object
(
[date] => 2019-05-06 00:00:00.000000
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(true)
So in order to make it equal to $date4 I need to subtract a negative interval instead of adding a positive one? How crazy is that?!
So the originally modified date with 5 weeks added is:DateTime Object
(
[date] => 2019-05-06 00:00:00
[timezone_type] => 3
[timezone] => Europe/London
)
1. positive DIFF and addition
diff is: + 1m 4d; days: 35
DateTime Object
(
[date] => 2019-05-05 00:00:00
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(false)
2. negative DIFF and addition
diff is: - 1m 5d; days 35DateTime Object
(
[date] => 2019-05-06 00:00:00
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(true)
So in order to make it equal to $date4 I need to subtract a negative interval instead of adding a positive one? How crazy is that?!
Output for 5.3.0 - 5.3.2
So the originally modified date with 5 weeks added is:DateTime Object
(
[date] => 2019-05-06 00:00:00
[timezone_type] => 3
[timezone] => Europe/London
)
1. positive DIFF and addition
diff is: + 1m 5d; days: 35
DateTime Object
(
[date] => 2019-05-06 00:00:00
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(true)
2. negative DIFF and addition
diff is: - 1m 5d; days 35DateTime Object
(
[date] => 2019-05-06 00:00:00
[timezone_type] => 3
[timezone] => Europe/London
)
is it equal to $date4? bool(false)
So in order to make it equal to $date4 I need to subtract a negative interval instead of adding a positive one? How crazy is that?!
Output for 5.2.10 - 5.2.17
Fatal error: Call to undefined method DateTime::createFromFormat() in /in/2MNE3 on line 5
Process exited with code 255.
Output for 5.2.0 - 5.2.9
Fatal error: Call to undefined method DateTime::createfromformat() in /in/2MNE3 on line 5
Process exited with code 255.
Output for 5.1.0 - 5.1.6
Fatal error: Class 'DateTime' not found in /in/2MNE3 on line 5
Process exited with code 255.
Output for 5.0.0 - 5.0.5
Fatal error: Call to undefined function date_default_timezone_set() in /in/2MNE3 on line 3
Process exited with code 255.
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected T_VARIABLE in /in/2MNE3 on line 6
Process exited with code 255.