<?php 
	echo "<h3>Example for __LINE__</h3>";  
	// print Your current line number i.e;4   
	echo "You are at line number " . __LINE__ . "<br><br>";
?>

<?php 
	echo "<h3>Example for __FILE__</h3>";  
	//print full path of file with .php extension  
	echo __FILE__ . "<br><br>";
?>

<?php 
	echo "<h3>Example for __DIR__</h3>";  
	//print full path of directory where script will be placed  
	echo __DIR__ . "<br><br>";
	//below output will equivalent to above one.
	echo dirname(__FILE__) . "<br><br>";  
?>

<?php 
	echo "<h3>Example for __FUNCTION__</h3>";  
	//Using magic constant inside function.  
	function test(){  
		//print the function name i.e; test. 
		echo 'The function name is '. __FUNCTION__ . "<br><br>"; 
	}  
	test();  
	
	//Magic constant used outside function gives the blank output.  
	function test_function(){  
		echo 'Hie';  
	}  
	test_function();  
	//give the blank output. 
	echo  __FUNCTION__ . "<br><br>";
?>

<?php 
	echo "<h3>Example for __CLASS__</h3>";  
	class JTP  
	{  
		public function __construct() {  
			;  
	}  
	function getClassName(){  
		//print name of the class JTP. 
		echo __CLASS__ . "<br><br>"; 
		}  
	}  
	$t = new JTP;  
	$t->getClassName();  
	
	//in case of multiple classes 
	class base
	{  
	function test_first(){  
			//will always print parent class which is base here.  
			echo __CLASS__; 
		}  
	}  
	class child extends base  
	{  
		public function __construct() {  
			;  
		}  
	}  
	$t = new child;  
	$t->test_first();  
?>

<?php 
	echo "<h3>Example for __TRAIT__</h3>";  
	trait created_trait {  
		function jtp(){  
			//will print name of the trait i.e; created_trait  
			echo __TRAIT__;
		}  
	}  
	class Company {  
		use created_trait;  
		}  
	$a = new Company;  
	$a->jtp();  
?>

<?php 
	echo "<h3>Example for __METHOD__</h3>";
	class method {  
		public function __construct() {  
			//print method::__construct  
				echo __METHOD__ . "<br><br>"; 
			}  
		public function meth_fun(){  
			//print method::meth_fun  
				echo __METHOD__; 
		}  
	}  
	$a = new method;  
	$a->meth_fun();
?>

<?php 
	echo "<h3>Example for __NAMESPACE__</h3>";
	class name {  
		public function __construct() {  
			echo 'This line will print on calling namespace.';   
		}   
	}  
	$class_name = __NAMESPACE__ . '\name';  
	$a = new class_name; 
?>

<?php 
	namespace Technical_Portal;
	echo "<h3>Example for CLASSNAME::CLASS </h3>";
	class TheDeveloperBlog {  
	}
	echo TheDeveloperBlog::class;    //ClassName::class 
?>