(PHP 4, PHP 5, PHP 7, PHP 8)
  PHP offers an alternative syntax for some of its control
  structures; namely, if,
  while, for,
  foreach, and switch.
  In each case, the basic form of the alternate syntax is to change
  the opening brace to a colon (:) and the closing brace to
  endif;, endwhile;,
  endfor;, endforeach;, or
  endswitch;, respectively.
  
<?php if ($a == 5): ?>
A is equal to 5
<?php endif; ?>
  In the above example, the HTML block "A is equal to 5" is nested within an
  if statement written in the alternative syntax.  The
  HTML block would be displayed only if $a is equal to 5.
 
  The alternative syntax applies to else and
  elseif as well.  The following is an
  if structure with elseif and
  else in the alternative format:
  
<?php
if ($a == 5):
    echo "a equals 5";
    echo "...";
elseif ($a == 6):
    echo "a equals 6";
    echo "!!!";
else:
    echo "a is neither 5 nor 6";
endif;
?>
Note:
Mixing syntaxes in the same control block is not supported.
   Any output (including whitespace) between a switch
   statement and the first case will result in a syntax
   error. For example, this is invalid:
  
<?php switch ($foo): ?>
    <?php case 1: ?>
    ...
<?php endswitch ?>
   Whereas this is valid, as the trailing newline after the
   switch statement is considered part of the closing
   ?> and hence nothing is output between the
   switch and case:
  
<?php switch ($foo): ?>
<?php case 1: ?>
    ...
<?php endswitch ?>
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