var_dump(3) [php man page]

VAR_DUMP(3)								 1							       VAR_DUMP(3)

var_dump - Dumps information about a variable

SYNOPSIS

       void var_dump (mixed  $expression, [mixed  $...])

DESCRIPTION

	This  function	displays  structured  information  about  one or more expressions that includes its type and value. Arrays and objects are
       explored recursively with values indented to show structure.

	All public, private and protected properties of objects will be returned in the output unless the object implements a __debugInfo() method
       (implemented in PHP 5.6.0).

       Tip

	      As  with anything that outputs its result directly to the browser, the output-control functions can be used to capture the output of
	      this function, and save it in a string (for example).

PARAMETERS

	      o $expression
		- The variable you want to dump.

RETURN VALUES

	No value is returned.

EXAMPLES

       Example #1

	      var_dump(3) example

	      <?php
	      $a = array(1, 2, array("a", "b", "c"));
	      var_dump($a);
	      ?>

	      The above example will output:

	      array(3) {
		[0]=>
		int(1)
		[1]=>
		int(2)
		[2]=>
		array(3) {
		  [0]=>
		  string(1) "a"
		  [1]=>
		  string(1) "b"
		  [2]=>
		  string(1) "c"
		}
	      }

	      <?php

	      $b = 3.1;
	      $c = true;
	      var_dump($b, $c);

	      ?>

	      The above example will output:

	      float(3.1)
	      bool(true)

SEE ALSO

       print_r(3), debug_zval_dump(3), var_export(3), __debugInfo().

PHP Documentation Group 													       VAR_DUMP(3)

SPLOBJECTSTORAGE(3)							 1						       SPLOBJECTSTORAGE(3)

The SplObjectStorage class

INTRODUCTION

	The  SplObjectStorage  class  provides	a map from objects to data or, by ignoring data, an object set. This dual purpose can be useful in
       many cases involving the need to uniquely identify objects.

CLASS SYNOPSIS

       SplObjectStorage

       SplObjectStorageCountableIteratorSerializableArrayAccess

       Methods

       o public void SplObjectStorage::addAll (SplObjectStorage  $storage)

       o public void SplObjectStorage::attach NULL (object  $object, [mixed  $data])

       o public bool SplObjectStorage::contains (object  $object)

       o public int SplObjectStorage::count (void  )

       o public object SplObjectStorage::current (void	)

       o public void SplObjectStorage::detach (object  $object)

       o public string SplObjectStorage::getHash (object  $object)

       o public mixed SplObjectStorage::getInfo (void  )

       o public int SplObjectStorage::key (void  )

       o public void SplObjectStorage::next (void  )

       o public bool SplObjectStorage::offsetExists (object  $object)

       o public mixed SplObjectStorage::offsetGet (object  $object)

       o public void SplObjectStorage::offsetSet NULL (object  $object, [mixed	$data])

       o public void SplObjectStorage::offsetUnset (object  $object)

       o public void SplObjectStorage::removeAll (SplObjectStorage  $storage)

       o public void SplObjectStorage::removeAllExcept (SplObjectStorage  $storage)

       o public void SplObjectStorage::rewind (void  )

       o public string SplObjectStorage::serialize (void  )

       o public void SplObjectStorage::setInfo (mixed  $data)

       o public void SplObjectStorage::unserialize (string  $serialized)

       o public bool SplObjectStorage::valid (void  )

EXAMPLES

       Example #1

	      SplObjectStorage as a set

	      <?php
	      // As an object set
	      $s = new SplObjectStorage();

	      $o1 = new StdClass;
	      $o2 = new StdClass;
	      $o3 = new StdClass;

	      $s->attach($o1);
	      $s->attach($o2);

	      var_dump($s->contains($o1));
	      var_dump($s->contains($o2));
	      var_dump($s->contains($o3));

	      $s->detach($o2);

	      var_dump($s->contains($o1));
	      var_dump($s->contains($o2));
	      var_dump($s->contains($o3));
	      ?>

	      The above example will output:

	      bool(true)
	      bool(true)
	      bool(false)
	      bool(true)
	      bool(false)
	      bool(false)

       Example #2

	      SplObjectStorage as a map

	      <?php
	      // As a map from objects to data
	      $s = new SplObjectStorage();

	      $o1 = new StdClass;
	      $o2 = new StdClass;
	      $o3 = new StdClass;

	      $s[$o1] = "data for object 1";
	      $s[$o2] = array(1,2,3);

	      if (isset($s[$o2])) {
		  var_dump($s[$o2]);
	      }
	      ?>

	      The above example will output:

	      array(3) {
		[0]=>
		int(1)
		[1]=>
		int(2)
		[2]=>
		int(3)
	      }

PHP Documentation Group 												       SPLOBJECTSTORAGE(3)