This is a list of reserved keywords in C++. Since they are used by the language, these keywords are not available for re-definition (or overloading) by programmers.
| Keyword | Description |
|---|---|
| asm | insert an assembly instruction |
| auto | declare a local variable |
| bool | declare a boolean variable |
| break | break out of a loop |
| case | a block of code in a switch statement |
| catch | handles exceptions from throw |
| char | declare a character variable |
| class | declare a class |
| const | declare immutable data or functions that do not change data |
| const_cast | cast from const variables |
| continue | bypass iterations of a loop |
| default | default handler in a case statement |
| delete | make dynamic memory available |
| do | looping construct |
| double | declare a double precision floating-point variable |
| dynamic_cast | perform runtime casts |
| else | alternate case for an if statement |
| enum | create enumeration types |
| explicit | only use constructors when they exactly match |
| export | allows template definitions to be separated from their declarations |
| extern | tell the compiler about variables defined elsewhere |
| false | a constant representing the boolean false value |
| float | declare a floating-point variable |
| for | looping construct |
| friend | grant non-member function access to private data |
| goto | jump to a different part of the program |
| if | execute code based on the result of a test |
| inline | optimize calls to short functions |
| int | declare an integer variable |
| long | declare a long integer variable |
| mutable | override a const variable |
| namespace | partition the global namespace by defining a scope |
| new | allocate dynamic memory for a new variable |
| operator | create overloaded operator functions |
| private | declare private members of a class |
| protected | declare protected members of a class |
| public | declare public members of a class |
| register | request that a variable be optimized for speed |
| reinterpret_cast | change the type of a variable |
| return | return from a function |
| short | declare a short integer variable |
| signed | modify variable type declarations |
| sizeof | return the size of a variable or type |
| static | create permanent storage for a variable |
| static_cast | perform a nonpolymorphic cast |
| struct | define a new structure |
| switch | execute code based on different possible values for a variable |
| template | create generic functions |
| this | a pointer to the current object |
| throw | throws an exception |
| true | a constant representing the boolean true value |
| try | execute code that can throw an exception |
| typedef | create a new type name from an existing type |
| typeid | describes an object |
| typename | declare a class or undefined type |
| union | a structure that assigns multiple variables to the same memory location |
| unsigned | declare an unsigned integer variable |
| using | import complete or partial namespaces into the current scope |
| virtual | create a function that can be overridden by a derived class |
| void | declare functions or data with no associated data type |
| volatile | warn the compiler about variables that can be modified unexpectedly |
| wchar_t | declare a wide-character variable |
| while | looping construct |