Reference - Parms functions - onceCall

App: regression/framework - Page: expressions/the_expression_of_echo_if_case_and_while_runs_once

PHP
expressions/the_expression_of_echo_if_case_and_while_runs_once.php HTML
expressions/the_expression_of_echo_if_case_and_while_runs_once.pad Result

<?php

  // The expression of {echo}, {if}, {case} and {while} runs once: it was evaluated when the
  // parameters were read and again by the tag, so a PHP call in it ran twice.

  $calls = 0;

  function onceCall () { return ++ $GLOBALS ['calls']; }

?>

{echo php:onceCall()}{if php:onceCall() gt 0}{/if}{case php:onceCall()}{when 3}{/case}{while php:onceCall() lt 0}{/while} {$calls}