Keywords

This page lists all of the C++ keywords, and either links to a reference page explaining their use, or provides a brief description.

List of Keywords

The C++ keywords are:

and, and_eq, asm, auto, bitand, bitor, bool, break, case, catch, char, class, compl, const, const_cast, continue, default, delete, do, double, dynamic_cast, else, enum, explicit, export, extern, false, float, for, friend, goto, if, inline, int, long, mutable, namespace, new, not, not_eq, operator, or, or_eq, private, protected, public, register, reinterpret_cast, return, short, signed, sizeof, static, static_cast, struct, switch, template, this, throw, true, try, typedef, typeid, typename, union, unsigned, using, virtual, void, volatile, wchar_t, while, xor, xor_eq

Boolean Operator Synonyms

• and is a synonym for &&.
• not is a synonym for !.
• not_eq is a synonym for !=.
• or is a synonym for ||.

Bitwise Operator Synonyms

• and_eq is a synonym for &=.
• bitand is a synonym for (bitwise) &.
• bitor is a synonym for |.
• compl is a synonym for ~.
• or_eq is a synonym for |=.
• xor is a synonym for ^.
• xor_eq is a synonym for ^=.

Constants

• true and false are the boolean constants.

Control Flow

• break can exit out of a switch statement or a for, do, or while loop.
• case defines alternatives in a switch statement.
• continue will move control flow to the next iteration of the enclosing for, do, or while loop.
• default defines the default alternative in a switch statement.
• do introduces a do loop.
• else is used in if statements.
• for introduces a for loop.
• goto jumps to a label.
• if introduces an if statement.
• return transfers flow to a function’s caller.
• switch introduces a switch statement.
• while introduces a while loop.

Types

The following keywords are used for built-in types.

• bool
• char
• double
• float
• int
• long
• short
• void (not really a type, but used in the absence of one)

The following keywords are used to introduce new types.

• enum

Qualifiers

• static can be used to declare persistent local variables; it has other uses not documented here.
• unsigned is used to specify an unsigned integral type. Examples: unsigned int, unsigned char.
• volatile is useful when declaring variables that may be modified by external interrupts.
• const is used to define constants.

Other

These keywords are not described in the Maple documentation. For more information, consult a C++ reference.

• asm is used to insert literal assembly language.
• auto is used to declare that a variable has automatic storage.
• catch is used in exception handling. Note that the default flags we pass to GCC include -fno-exceptions.
• class is used to define classes.
• const_cast is used in typecasting.
• delete is used to free new-allocated storage. Note that dynamic memory allocation is not available by default on the Maple, so you’ll have to bring your own new and delete if you want this.
• dynamic_cast is used in typecasting.
• explicit is used to declare constructors that can be called only explicitly.
• export declares a template definition accessible to other compilation units.
• extern can mark a declaration as a declaration and not a definition, and also grant external linkage to a const or typedef.
• friend is used to declare that certain functions have access to a class’s private variables.
• inline is a compiler hint to inline a function.
• mutable specifies that a member can be updated, even when a member of a const object.
• namespace declares a new namespace.
• new dynamically allocates space for a value. Note that dynamic memory allocation is not available by default on the Maple, so you’ll have to bring your own new and delete if you want this.
• operator is used to define type-specific operator overrides.
• private declares a private class member.
• protected declares a protected class member.
• public declares a public class member.
• register is a compiler hint to store a variable in a register.
• reinterpret_cast is used in typecasting.
• signed is the opposite of unsigned.
• static_cast is used in typecasting.
• struct declares a new struct.
• template introduces a template class, function, etc.
• this is a pointer to the receiver object.
• throw is used in exception handling. Note that the default flags we pass to GCC include -fno-exceptions.
• try is used in exception handling. Note that the default flags we pass to GCC include -fno-exceptions.
• typedef defines a type synonym.
• union defines an untagged union.
• using is a directive related to namespaces.
• virtual declares a method which may be overridden.
• wchar_t is the wide character type.