update php8 course

README.md

@@ -45,17 +45,19 @@ Use the Linux for Composer Tools to create the two config files as follows:
 * Copy the `/path/to/repo/templates/creds.json.dist`:
 ```
 cd /path/to/repo
-cp templates/creds.json.dist ./creds.json`
+cp templates/creds.json.dist ./creds.json
 ```
 * Modify `/path/to/repo/creds.json` as follows:
-| Replace ... | With ... |
-| :---------- | :------- |
-| %FORK%%     | ... the URL value represented by `%%FORK%%` which you wrote down in an earlier step above |
+
+| Replace ...      | With ... |
+| :--------------- | :------- |
+| %%FORK%%         | ... the URL value represented by `%%FORK%%` which you wrote down in an earlier step above |
 | %%GITHUB_EMAIL%% | ... your github.com email address |
-| %%GITHUB_NAME%% | ... your github.com account name |
-| %%ACCOUNT%% | ... your Linux for PHP Cloud Services account name (all lowercase) |
-| %%USER%% | ... your Linux for PHP Cloud Services login name (email address) |
-| %%TOKEN%% | ... your Linux for PHP Cloud Services access token |
+| %%GITHUB_NAME%%  | ... your github.com account name |
+| %%ACCOUNT%%      | ... your Linux for PHP Cloud Services account name (all lowercase) |
+| %%USER%%         | ... your Linux for PHP Cloud Services login name (email address) |
+| %%TOKEN%%        | ... your Linux for PHP Cloud Services access token |
+
 * Run the Linux for Composer Tools command to generate the two config files:
   * Commands if you're running on Linux:
 ```

examples/core_cool_mixed.php

@@ -0,0 +1,18 @@
+<?php
+// core_cool_mixed.php
+
+function old_style($a)
+{
+	return $a;
+}
+
+function new_style(mixed $a) : mixed
+{
+	return $a;
+}
+
+$reflect[] = new ReflectionFunction('old_style');
+$reflect[] = new ReflectionFunction('new_style');
+
+foreach ($reflect as $item) echo $item . "\n";
+

examples/core_cool_mixed_covar_no.php

@@ -0,0 +1,29 @@
+<?php
+// core_cool_mixed_covar_no.php
+// demonstrates violation of LSP rules
+
+class Upper
+{
+	public mixed $phrase;
+	public function wide(string $a)
+	{
+		return base64_encode($a);
+	}
+	public function narrow(mixed $a)
+	{
+		return base64_decode($a);
+	}
+}
+class Middle extends Upper
+{
+	// this does NOT work
+	public function narrow(string $a)
+	{
+		return base64_decode($a);
+	}
+}
+class Finger extends Upper
+{
+	// this does NOT work
+	public string $phrase
+}

examples/core_cool_mixed_covar_ok.php

@@ -0,0 +1,33 @@
+<?php
+// core_cool_mixed_covar_ok.php
+// demonstrates co-variance support
+
+class Upper
+{
+	public function wide(string $a)
+	{
+		return base64_encode($a);
+	}
+	public function narrow(mixed $a)
+	{
+		return base64_decode($a);
+	}
+}
+class Middle extends Upper
+{
+	// this works OK
+	public function wide(mixed $a)
+	{
+		return parent::wide($a);
+	}
+}
+
+$phrase = 'FCF Continuous Learning';
+$middle = new Middle();
+$encoded = $middle->wide($phrase);
+$decoded = $middle->narrow($encoded);
+
+echo "\nOriginal: $phrase\n";
+echo "\nBase 64 : $encoded\n";
+echo "\nDecoded : $decoded\n";
+

examples/core_cool_mixed_variance.php

@@ -0,0 +1,42 @@
+<?php
+// core_cool_mixed_variance.php
+// demonstrates co-variance support
+
+class Upper
+{
+	public function wide(string $a)
+	{
+		return base64_encode($a);
+	}
+	public function narrow(mixed $a)
+	{
+		return base64_decode($a);
+	}
+}
+class Middle extends Upper
+{
+	// this works OK
+	public function wide(wide $a)
+	{
+		return parent::wide($a);
+	}
+}
+class Finger extends Upper
+{
+	// this does not work
+	public function narrow(string $a)
+	{
+		return parent::narrow($a);
+	}
+}
+
+$phrase = 'FCF Continuous Learning';
+$middle = new Middle();
+$finger = new Finger();
+$encoded = $middle->wide($phrase);
+$decoded = $finger->narrow($encoded);
+
+echo "\nOriginal: $phrase\n";
+echo "\nBase 64 : $encoded\n";
+echo "\nDecoded : $decoded\n";
+

examples/core_cool_nullsafe.php

@@ -0,0 +1,24 @@
+<?php
+// core_cool_nullsafe.php
+
+// set up autoloader
+include __DIR__ . '/src/Loader.php';
+$loader = new Loader(__DIR__ . '/src');
+
+use Application\Entity\Event;
+$event_key = 'DOG-LOV-RC-885';
+$dsn = 'mysql:host=localhost;dbname=phpcl';
+$pdo = new PDO($dsn, 'phpcl', 'password');
+
+// event exists
+$event = new Event($pdo, $event_key);
+echo 'Event:' . $event->getProp('event_name') . PHP_EOL;
+echo 'Hotel:' . $event->getHotel()->getProp('hotelName');
+echo "\n";
+
+// event does not exist
+$event = new Event($pdo, 'BAD-KEY');
+echo 'Event:' . $event?->getProp('event_name') . PHP_EOL;
+echo 'Hotel: ' . $event?->getHotel()?->getProp('hotelName');
+echo "\n";
+

examples/core_cool_nullsafe_fail.php

@@ -0,0 +1,20 @@
+<?php
+// core_cool_nullsafe_fail.php
+// demonstrates short circuiting
+
+$arr1 = array_combine(range('A','F'), range(111,700,111));
+$arrObj = new ArrayObject($arr1);
+$arr2 = ['A' => $arrObj, 'B' => NULL];
+$anon = new class ($arr2) {
+        public $prop;
+        public function __construct($arr)
+        {
+                $this->prop = new stdClass();
+                $this->prop->arr = $arr;
+        }
+};
+$arr3 = ['anon' => $anon ];
+echo $arr3['anon']->prop->arr['A']['A'];
+echo "\n";
+echo $arr3['anon']?->prop->arr['B']['A'] ?? 'DEFAULT';
+echo "\n";

examples/core_cool_static_return.php

@@ -0,0 +1,13 @@
+<?php
+// core_cool_static_return.php
+
+// autoloader
+include __DIR__ . '/src/Loader.php';
+use Application\Sql\Insert;
+$loader = new Loader(__DIR__ . '/src');
+$insert = new Insert();
+
+echo $insert->into('images')
+			->columns(['title','image'])
+			->values(['Apple', '/images/dbierer/apple.png'])
+			->render();

examples/core_cool_variadic.php

@@ -0,0 +1,10 @@
+<?php
+// core_cool_variadic.php
+class Upper {
+        public function test(int $many, string $parameters, $here) {}
+}
+class Lower extends Upper {
+        public function test(...$everything) {}
+}
+$lower = new Lower();
+var_dump($lower);

examples/core_cool_weak_map.php

@@ -0,0 +1,28 @@
+<?php
+// core_cool_weak_map.php
+
+// initialize two "expensive" objects
+$expensive1 = new ArrayObject(range('A','F'));
+$expensive2 = new ArrayObject(range('A','F'));
+
+// store with SplObjectStorage
+echo "\nSplObjectStorage Before:\n";
+$storage = new SplObjectStorage();
+$storage->offsetSet($expensive1, 111);
+var_dump($storage);
+
+// the object is not unset as a reference exists 
+unset($expensive1);
+echo "\nSplObjectStorage After:\n";
+var_dump($storage);
+
+// store with WeakMap
+echo "\nWeakMap Before:\n";
+$weakmap = new WeakMap();
+$weakmap->offsetSet($expensive2, 222);
+var_dump($weakmap);
+
+// the object is allow to go away as only a weak reference exists 
+unset($expensive2);
+echo "\nWeakMap After:\n";
+var_dump($weakmap);

examples/core_cool_weak_ref.php

@@ -0,0 +1,18 @@
+<?php
+// core_cool_weak_ref.php
+$obj1 = new ArrayObject([1,2,3]);
+$obj2 = $obj1;
+$obj3 = new ArrayObject(['A','B','C']);
+
+echo 'If we create a _weak reference_ to $obj` and then destroy it,' . PHP_EOL;
+echo 'it doesn\'t go away because of `$obj2`:' . PHP_EOL;
+$weakref = WeakReference::create($obj1);
+var_dump($weakref->get());  // object exists
+unset($obj1);
+var_dump($weakref->get());  // object exists
+
+echo "\n" . 'On the other hand, the weak reference to `$obj3` goes away after calling `unset()`' . "\n";
+$weakref = WeakReference::create($obj3);
+var_dump($weakref->get());  // object exists
+unset($obj3);
+var_dump($weakref->get());  // NULL

examples/core_ext_curl.php

@@ -8,4 +8,6 @@
 	echo "This works in PHP 7\n";
 } elseif ($ch instanceof CurlHandle) {
 	echo "This works in PHP 8\n";
+	$reflect = new ReflectionObject($ch);
+	echo $reflect . "\n";
 }

examples/core_ext_datetime_zone.php

@@ -0,0 +1,24 @@
+<?php
+// core_ext_datetime_zone.php
+
+date_default_timezone_set('America/New_York');
+
+// forward clock changes
+$date[] = new DateTime('2021-03-14 01:30:00');
+$date[] = new DateTime('2021-03-14 02:30:00');
+$date[] = new DateTime('2021-03-14 03:30:00');
+
+// backwards clock changes
+$date[] = new DateTime('2021-11-07 01:30:00');
+
+try {
+	$date[] = new DateTime('2021-11-07 01:30:00 ST');
+	$date[] = new DateTime('2021-11-07 01:30:00 DST');
+} catch (Throwable $t) {
+	echo get_class($t) . ':' . $t->getMessage();
+	echo "\n";
+}
+
+foreach ($date as $obj)
+    echo $obj->format('Y-m-d H:i:s T') . "\n";
+

examples/core_ext_datetimeinterface.php

@@ -0,0 +1,14 @@
+<?php
+// core_ext_datetimeinterface.php
+
+$dt[] = $obj = new DateTime('now');
+$dt[] = $imm = new DateTimeImmutable('now');
+
+try {
+	$dt[] = DateTime::createFromImmutable($imm);
+	$dt[] = DateTimeImmutable::createFromInterface($dt);
+} catch (Throwable $t) {
+	echo get_class($t) . ':' . $t->getMessage();
+	echo "\n";
+}
+var_dump($dt);

examples/core_imp_expr_new.php

@@ -1,25 +1,19 @@
 <?php
-// core_imp_expr_new.php
-class Base {
-	public array $data;
-	public function __construct($data = []) {
-		$this->data = $data;
-	}
+// generate_primes.php
+$start = microtime(TRUE);
+$max = 100000;
+for ($x = 5; $x < $max; $x++) {
+    // This if evaluation checks to see if number is odd or even
+    $test = TRUE;
+    for($i = 3; $i < $x; $i++) {
+        if(($x % $i) === 0) {
+            $test = FALSE;
+            break;
+        }
+    }
+    if ($test) echo $x . ', ';
 }
-class JsonResponse extends Base {
-	public function render() {
-		header('Content-Type: application/json');
-		return json_encode($this->data);
-	}
-}
-class TextResponse extends Base {
-	public function render() {
-		header('Content-Type: text/html');
-		return var_export($this->data, TRUE);
-	}
-}
-$accept = $argv[1] ?? 'text';
-$data = ['A' => [1,2,3],'B' => [4,5,6],'C' => [7,8,9]];
-$strategies = ['text' => 'TextResponse','json' => 'JsonResponse'];
-$response = new ($strategies[$accept] ?? 'JsonResponse')($data);
-echo $response->render();
+echo "all prime numbers\n";
+$end = microtime(TRUE);
+$run = ($end - $start) / 1000000;
+echo "Run Time: $run seconds\n";