compact(3) [php man page]

COMPACT(3)								 1								COMPACT(3)

compact - Create array containing variables and their values

SYNOPSIS

       array compact (mixed  $varname1, [mixed	$...])

DESCRIPTION

	Creates an array containing variables and their values.

	For  each  of  these, compact(3) looks for a variable with that name in the current symbol table and adds it to the output array such that
       the variable name becomes the key and the contents of the variable become the value for that  key.  In  short,  it  does  the  opposite	of
       extract(3).

	Any strings that are not set will simply be skipped.

PARAMETERS

	      o $varname1
		-compact(3)  takes  a variable number of parameters. Each parameter can be either a string containing the name of the variable, or
		an array of variable names. The array can contain other arrays of variable names inside it; compact(3) handles it recursively.

RETURN VALUES

	Returns the output array with all the variables added to it.

EXAMPLES

       Example #1

	      compact(3) example

	      <?php
	      $city  = "San Francisco";
	      $state = "CA";
	      $event = "SIGGRAPH";

	      $location_vars = array("city", "state");

	      $result = compact("event", "nothing_here", $location_vars);
	      print_r($result);
	      ?>

	      The above example will output:

	      Array
	      (
		  [event] => SIGGRAPH
		  [city] => San Francisco
		  [state] => CA
	      )

NOTES

       Note

	      Gotcha

	       Because variable variables may not be used with PHP's Superglobal arrays within functions, the Superglobal arrays may not be passed
	      into compact(3).

SEE ALSO

       extract(3).

PHP Documentation Group 														COMPACT(3)

LIST(3) 								 1								   LIST(3)

list - Assign variables as if they were an array

SYNOPSIS

       array list (mixed  $var1, [mixed  $...])

DESCRIPTION

	Like array(3), this is not really a function, but a language construct. list(3) is used to assign a list of variables in one operation.

PARAMETERS

	      o $var1
		- A variable.

RETURN VALUES

	Returns the assigned array.

EXAMPLES

       Example #1

	      list(3) examples

	      <?php

	      $info = array('coffee', 'brown', 'caffeine');

	      // Listing all the variables
	      list($drink, $color, $power) = $info;
	      echo "$drink is $color and $power makes it special.
";

	      // Listing some of them
	      list($drink, , $power) = $info;
	      echo "$drink has $power.
";

	      // Or let's skip to only the third one
	      list( , , $power) = $info;
	      echo "I need $power!
";

	      // list() doesn't work with strings
	      list($bar) = "abcde";
	      var_dump($bar); // NULL
	      ?>

       Example #2

	      An example use of list(3)

	      <table>
	       <tr>
		<th>Employee name</th>
		<th>Salary</th>
	       </tr>

	      <?php
	      $result = $pdo->query("SELECT id, name, salary FROM employees");
	      while (list($id, $name, $salary) = $result->fetch(PDO::FETCH_NUM)) {
		  echo " <tr>
" .
			"  <td><a href="info.php?id=$id">$name</a></td>
" .
			"  <td>$salary</td>
" .
			" </tr>
";
	      }

	      ?>

	      </table>

       Example #3

	      Using nested list(3)

	      <?php

	      list($a, list($b, $c)) = array(1, array(2, 3));

	      var_dump($a, $b, $c);

	      ?>

	      int(1)
	      int(2)
	      int(3)

       Example #4

	      Using list(3) with array indices

	      <?php

	      $info = array('coffee', 'brown', 'caffeine');

	      list($a[0], $a[1], $a[2]) = $info;

	      var_dump($a);

	      ?>

	       Gives the following output (note the order of the elements compared in which order they were written in the list(3) syntax):

	      array(3) {
		[2]=>
		string(8) "caffeine"
		[1]=>
		string(5) "brown"
		[0]=>
		string(6) "coffee"
	      }

NOTES

       Warning

	      list(3)  assigns	the values starting with the right-most parameter. If you are using plain variables, you don't have to worry about
	      this. But if you are using arrays with indices you usually expect the order of the indices in the array the same you  wrote  in  the
	      list(3) from left to right; which it isn't. It's assigned in the reverse order.

       Warning

	       Modification of the array during list(3) execution (e.g. using list($a, $b) = $b) results in undefined behavior.

       Note

	      list(3) only works on numerical arrays and assumes the numerical indices start at 0.

SEE ALSO

       each(3), array(3), extract(3).

PHP Documentation Group 														   LIST(3)