Appendix E. PHP reserved words

Here is the list of PHP reserved words, usually constants and predefined variables. You won't find any functions here, but rather language constructs. You shouldn't try to use such names as variable, function, constant or method names, as it will surely lead to confusion.

and E_PARSE old_function
$argv E_ERROR or
as E_WARNING parent
$argc eval PHP_OS
break exit() $PHP_SELF
case extends PHP_VERSION
cfunction FALSE print()
class for require()
continue foreach require_once()
declare function return
default $HTTP_COOKIE_VARS static
do $HTTP_GET_VARS switch
die() $HTTP_POST_VARS stdClass
echo() $HTTP_POST_FILES $this
elseif $HTTP_SERVER_VARS var
empty() if xor
enddeclare include() virtual()
endfor include_once() while
endforeach global __FILE__
endif list() __LINE__
endswitch new __sleep
endwhile not __wakeup