A - Keywords
This is the list of keywords reserved by C++. This means these words cannot be used as an identifier for variables, functions, class/struct member names etc.. Some are reserved with no current or deprecated usecase.
Currently in Use
| Keyword | Description |
|---|---|
alignas (C++11) | |
and | |
and_eq | |
asm | |
auto | |
bitand | |
bitor | |
break | |
case | |
catch | |
class | |
compl | |
concept (C++20) | |
const | |
consteval (C++20) | |
constexpr (C++11) | |
constinit (C++20) | |
continue | |
co_await (C++20) | |
co_return (C++20) | |
co_yield (C++20) | |
decltype (C++11) | |
default | |
do | |
double | |
else | |
enum | |
explicit | |
export | |
extern | |
false | |
float | |
for | |
friend | |
goto | |
if | |
inline | |
mutable | |
namespace | |
noexcept (C++11) | |
not | |
not_eq | |
nullptr (C++11) | |
operator | |
or | |
or_eq | |
private | |
protected | |
public | |
register | |
requires (C++20) | |
return | |
signed | |
sizeof | |
static | |
static_assert (C++11) | |
struct | |
switch | |
template | |
this | |
thread_local (C++11) | |
throw | |
true | |
try | |
typedef | |
typename | |
union | |
unsigned | |
using | |
virtual | |
void | |
volatile | |
while | |
xor | |
xor_eq |
Reserved In Specific Contexts
These keywords are reserved in specific circumstances like in a class declaration etc..
| Keyword | Description |
|---|---|
final (C++11) | Specifies virtual member function cannot be overridden in child class. |
override (C++11) | Specifies virtual member function definition overrides parent definition. |
import (C++20) | Module import declaration. |
module (C++20) | Module and module fragment declaration. |
Reserved for Future Use
These keywords are reserved for experimental features being tested in a Technical Specification.
| Keyword | Technical Specification | Description |
|---|---|---|
atomic_cancel | Transactional Memory (TM) TS | Starts atomic block that will restore data modified during atomic block for some exception types, otherwise it will call std::abort. |
atomic_commit | Transactional Memory (TM) TS | Starts atomic block that commits data changes regardless of exceptions being thrown. |
atomic_noexcept | Transactional Memory (TM) TS | Starts atomic block that will call std::abort if exception is thrown within the block. |
reflexpr | Reflection TS | Provides meta info about an object by returning a meta-object. |
synchronized | Transactional Memory (TM) TS | Starts a synchronized block |
transaction_safe | Transactional Memory (TM) TS | Indicates that a function is transaction-safe. |
transaction_safe_dynamic | Transactional Memory (TM) TS | Indicates that a virtual function is transaction-safe. |