The document contains PHP code snippets demonstrating various programming concepts, including function definitions, anonymous functions (closures), and class implementations. Key examples include calculating factorials, simulating a 'car' class with methods for actions, and using the invoke method in classes. It showcases different scope handling in closures and how to utilize constructors and magic methods in object-oriented programming.

3. flickr.com/photos: katkun/4349837202/By katkun

18. LOG.PHP:
1. define("DEPOSIT",100);
2. /**
3. * getParams()
4. * returns annual interest and how many hundreds
5. **/
6. function getParams() {
7. $annual_interest = 0.05;
8. $hundreds = 2;
9. if ( isset( $_GET['ai'] ) ) {
10.$annual_interest = (float) $_GET['ai'];
11.}
12.if (isset( $_GET['hu'] ) ) {
13.$hundreds = (int) $_GET['hu'];
14.}
15.return array($annual_interest,$hundreds);
16.}
17.list ($annual_interest, $hundreds) = getParams();
18.$percent_format = substr($annual_interest,-1,1) . '%';
19.$rate = 1 + $annual_interest;
20./** REMOVED:
21.* $f = create_function('$x, $y', 'return round( log( $x ) / log( $y ),2 );' );
22.*
23.**/
24.$f = function( $x, $y ) {
25.return round( log( $x ) / log( $y ), 2 );
26.};
27.$x = $f( $hundreds, $rate );

45. THIS_AND_THAT.PHP:
1. <?php
2. class Example2 {
3. private $secret_code = " <--{ -*- }--> ";
4. function Square( $num ) {
5. return $num * $num;
6. }
7. function getSecretSign()
8. {
9. return $this->secret_code;
10.}
11.function doIt( $x ) {
12.$that = $this;
13.return function ($y) use ($x, $that) {
14.$special = $that->getSecretSign();
15.return $special . ($that->Square( $x ) + $y) . $special;
16.};
17.}
18.}
19.$e2 = new Example2();
20.$r = $e2->doIt( 10 );
21.$rr = $r( 80 );
22.include("this_and_that.template.php");

49. DIFFERENT_SCOPES.PHP:
1. <?php
2. include("lvd.header.php");
3. ?>
4. <script>
5. var fact = function(n) {
6. if( n <= 1 ){
7. return 1;
8. }
9. else
10.{
11.return n * fact( n-1 );
12.}
13.};
14.alert( fact( 4 ) );
15.</script>
16.<?php
17.$fact = function( $n ){
18.if( $n <= 1 ) {
19.return 1;
20.} else {
21.return $n * $fact( $n-1 );
22.}
23.};
24.$r = $fact( 4 ); // Output : Error
25.include("lvd.footer.php");

51. DIFFERENT_SCOPES_GOOD.PHP:
1. <?php include("lvd.header.php"); ?>
2. <script>
3. var fact = function( n ) {
4. if( n <= 1 ){
5. return 1;
6. } else {
7. return n * fact( n-1 );
8. }
9. };
10.alert(fact(4))
11.</script>
12.<?php
13.$fact = function( $n ) use( &$fact ) {
14.if($n <= 1) {
15.return 1;
16.}
17.else
18.{
19.return $n * $fact( $n-1 );
20.}
21.};
22.$r = $fact( 4 );
23.include("lvd.footer.php");

53. FERRARI.PHP:
1. <?php
2. // modified 1-24-2011
3. // more info at
http://www.ibm.com/developerworks/opensource/library/os-php-
lambda/index.html?ca=drs-
4. class Car {
5. private $model;
6. public $Drive;
7. public function __construct( $model )
8. {
9. $this->model = $model;
10.}
11.public function __call( $method, $args ) {
12.return call_user_func_array( $this->$method, $args );
13.}
14.public function __get($name) {
15.return $this->$name;
16.}
17.}
18.$car = new Car("Ferrari");
19.$car->Drive = function( $speed ) use ( $car ) {
20.return 'Varoom! ' . $car->model . ' is driving ' . $speed . ' mph and
loving it.';
21.};
22.$r = array();
23.$r[0] = $car->Drive("90");
24.$go_for_it = $car->Drive;
25.unset( $car );
26.$r[1] = $go_for_it("120");
27.include("ferrari.template.php");

60. INVOKE_EXAMPLE.PHP:
1. <?php
2. class Determinator {
3. public $x;
4. public function __construct( $x ) {
5. $this->x = (int) $x;
6. }
7. public function __invoke() {
8. $res = ($this->x % 2 == 1)? ' odd': 'even';
9. return " // $d->x is $res <span style='font: 70% Arial,Helvetica'>
( " . $this->x . " )</span>";
10.}
11.}
12.$num = pow(3,4) - 5;
13.$d = new Determinator( $num );
14.$r[] = $d();
15.$d->x = pow(4,3) - 7;
16.$r[] = $d->__invoke() . '<br>';
17.include("invoke_example.template.php");

62. FERRARI2.PHP:
1. <?php
2. // modified 1-24-2011
3. class Car {
4. private $model;
5. public function __construct( $model )
6. {
7. $this->model = $model;
8. }
9. public function __get($name) {
10.return $this->$name;
11.}
12.public function Action( Closure $act, $speed=null ) {
13.return $act($speed);
14.}
15.}
16.$car = new Car("Ferrari");
17.$closure = function( $speed ) use ( $car ) {
18.return 'Varoom! ' . $car->model . ' is driving ' . $speed . ' mph and
loving it.';
19.};
20.$lambda = function() {
21.return "<strong>Hellow, World!</strong>";
22.};
23.$r = array();
24.$r[0] = $car->Action( $lambda );
25.$r[1] = $car->Action( $closure, "135");
26.include("ferrari.template2.php");