My copy of the manual prepends those statements with:
"Prior to PHP 4.0.2, the following applies:"
According to Zeev Suraski (who probably should know these things, if anyone does), "as of PHP 4.0.3, the implementation of require() processes the file 'just in time'"
(
http://marc.theaimsgroup.com/?l=php-...97419027907315)
i.e. only if needed. So, nowadays, the lines:
if(false){
require("page.php");
}
Will neither read nor execute page.php. Ever. This is actually how include always behaved.
HTH
Dan