List of Keywords

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- List of Reserved Words
- List of Keywords

## List of Keywords

These words have special meaning in PHP. Some of them represent things which look like functions, some look like constants, and so on - but they're not, really: they are language constructs. The following words cannot be used as constants, class names, or function names. They are, however, allowed as property, constant, and method names of classes, interfaces and traits, except that `class` may not be used as constant name.

PHP Keywords
__halt_compiler() | abstract | and | array() | as
break | callable | case | catch | class
clone | const | continue | declare | default
die() | do | echo | else | elseif
empty() | enddeclare | endfor | endforeach | endif
endswitch | endwhile | eval() | exit() | extends
final | finally | fn (as of PHP 7.4) | for | foreach
function | global | goto | if | implements
include | include_once | instanceof | insteadof | interface
isset() | list() | match (as of PHP 8.0) | namespace | new
or | print | private | protected | public
readonly (as of PHP 8.1.0) * | require | require_once | return | static
switch | throw | trait | try | unset()
use | var | while | xor | yield
yield from |  |  |  |

* `readonly` may be used as function name.

Compile-time constants
__CLASS__ | __DIR__ | __FILE__ | __FUNCTION__ | __LINE__ | __METHOD__
__NAMESPACE__ | __TRAIT__ |  |  |  |