C++ glossary by Stroustrup

>>

(1) iostream input operator. TC++PL 3.6, 21.3.2, D&E 8.3.1. (2) integer right-shift operator. TC++PL 6.2.

<<

(1) iostream output operator. TC++PL 3.4, 21.2.1, D&E 8.3.1. (2) integer left-shift operator. TC++PL 6.2.

static

(1) keyword used to declare a class member static; meaning allocated in static memory. For a member function, this implies that there is no this pointer. (2) keyword used to specify that a local variable should be allocated in static memory. (3) deprecated: keyword used to specify that a global name should not be visible from other translation units. TC++PL 7.1.2, 10.2.4, 10.4.8-9.

stack

(1) memory used to hold local variables for a function. (2) standard library first-in-last-out sequence. TC++PL 10.4.3, 17.3.1, D&E 2.3, 3.9.

Max Munch

(1) mythical participant in the C++ standards process. (2) the rule that says that while parsing C++ always chooses the lexically or syntactically longest alternative. Thus ++ is the increment operation, not two additions, and long int is a single integer type rather than the long integer followed by an int. Cross references in this glossary follow this rule.

container

(1) object that holds other objects. (2) type of object that holds other objects. (3) template that generates types of objects that hold other objects. (4) standard library template such as vector, list, and map. TC++PL 16.2, 16.2.3, 17, D&E 15.3.

iostream

(1) standard library flexible, extensible, type-safe input and output framework. (1) stream that can be used for both input and output. See also: file stream, string stream. TC++PL 3.4, 3.6, 21, D&E 3.11.4.1, 8.3.1.

source file

.c file or header.

C++/CLI

A set of Microsoft extensions to C++ for use with their .Net system. See FAQ comments.

built-in type

A type provided directly by C++, such as int, double, and char*. See also: integral types, floating-point type, pointer, reference. TC++PL 4.1.1, 5.1, 5.2, 5.5, D&E 4.4, 15.11.3.

Ritchie

Dennis Ritchie is the designer and original implementer of C. Co-author of Kernighan & Ritchie: "The C programming Language".

GNU C++

GNU's implementation of C++.

placement delete

See explicit call of destructor.

value return

The semantics of function return is to pass a copy of the return value. The copy operation is defined by the return type's copy constructor. TC++PL 7.4.

public base

a base class declared public in a derived class, so that the base's public members are accessible to the users of that derived class. TC++PL 15.3.2, D&E 2.3.

superclass

a base class.

infix operator

a binary operator where the operator appears between the operands. For example, a+b.

crosscast

a cast from a class to a sibling class. See also: dynamic_cast, upcast, downcast. TC++PL 15.4.

derived class

a class with one or more base classes TC++PL 2.6.2, 12, 15, D&E 3.5.

software

a collection of programs

WG21

a common abbreviation of the name of the ISO C++ standards committee.

copy constructor

a constructor accepting an object of the class itself as its argument, typically Z::Z(const Z&). A copy constructor is used for initialization of objects of type T with objects of type T. If a copy constructor is not declared for a class, memberwise initialization is used. See also: call-by-value, argument passing, value return, copy assignment. TC++PL 10.4.4.1, 10.4.6.3, D&E 11.4.

function parameter

a parameter of a function.

translation unit

a part of a program that can be separately compiled. TC++PL 9.1.

virtual-function pointer

a pointer to a class' virtual function table.

bitset

a standard library "almost container" holding N bits and providing logical operations on those. TC++PL 17.5.3.

iterator

a standard library abstraction for objects referring to elements of a sequence. TC++PL 3.8.1, 19.2-3.

loop

a statement that expresses the notion of doing something zero or more times, such as a for-statement and a while-statement.

stringstream

a string stream for input and output.

collection

a term sometimes used as a synonym for container.

enumeration

a user-defined type consisting of a set of named values. TC++PL 4.8, D&E 11.7.

resource management

a way of acquiring and releasing a resource, such as memory, thread, or file. See also: resource acquisition is initialization, auto_ptr, vector. TC++PL 14.4, D&E 10.4.

private

access control keyword. See private member, private base.

aggregate

an array or a struct without a constructor.

mutable

an attribute of a member that makes it possible to change its value even if its object is declared to be const TC++PL 10.2.7.2, D&E 13.3.3.

lvalue

an expression that may appear on the left-hand side of an assignment; for example, v[7] if v is an array or a vector. An lvalue is modifiable unless it is const. TC++PL 4.9.6, D&E 3.7.1.

rvalue

an expression that may appear on the right-hand side of an assignment, but not of the left-hand side; for example, 7. D&E 3.7.1.

ifstream

an file stream for input.

Simula

ancestor of C++ designed by Ole-Johan Dahl and Kristen Nygaard; the source of the C++ class concept. TC++PL 1.4, 2.6.2, D&E 1.1, 3.1.

const

attribute of a declaration that makes the entity to which it refers readonly. See also: const member function. TC++PL 5.4, D&E 3.8.

C-style cast

dangerous form of explicit type conversion; prefer new-style cast if you must use explicit type conversion. TC++PL 6.2.7, D&E 14.3.5.1.

variable definition

declaration of a named object of a data type without an extern specifier.

strstream

deprecated ancestor of stringstream.

double

double-precision floating-point number. TC++PL 4.5.

deprecated feature

feature left in a programming language for historical reasons only. The standard s committee recommends against its use and warns that it may be removed in future revisions of the standard.

inline function

function declared inline using the inline keyword or by being a member function defined in-class. Compilers are encouraged to generate inline code rather than function calls for inline functions. Most benefits from inlining comes with very short functions. TC++PL 7.1.1, 9.2, 10.2.9, D&E 2.4.1 .

basic_string

general standard-library string template parameterized by character type. See also: string, C-style string. TC++PL 20.3.

hash_map

hashed contained based on the standard library framework. Not (yet) part of the standard but very common in libraries based on the standard library. See also: map, vector, list. TC++PL 17.6.

for-statement

iteration statement specifying an initializer, an iteration condition, a "next-iteration" operation, and a controlled statement. TC++PL 6.3.3.

in-class

lexically within the declaration of a class. TC++PL 10.2.9, 10.4.6.2.

constant

literal, object or value declared const, or enumerator.

argument-based lookup

lookup of a function name or operator based on the namespace of the arguments or operands. Often called Koenig lookup after Andrew Koenig who proposed the scheme to the standards committee. TC++PL 8.2.6, 11.2.4, C.13.8.4.

static member

member of a class for which there is only one copy for the whole program rather than one per object. TC++PL 10.2.4, D&E 13.4.

non-static member

member of a class that is not declared to be a static member. An object of a class has its own space for each non-static data member.

destructor

member of a class used to clean up before deleting an object. It's name is its class' name prefixed by '~'. For example, Foo's destructor is ~Foo(). Often used to release resources. A destructor is implicitly called whenever an object goes out of scope or is deleted. See also: virtual destructor, order of destruction. TC++PL 10.4.2, D&E 2.11.1, 3.11.2.

static memory

memory allocated by the linker. TC++PL 10.4.3, D&E 2.3, 2.11.1, 3.9, 11.4.2.

qualified name

name qualified by the name of its enclosing class or namespace using the scope resolution operator ::. For example, std::vector or ::main. TC++PL 4.9.3, 8.2.1, 10.2.4, 15.2.1, 15.2.2, D&E 3.11.3.

allocator

object used by standard library containers to allocate and deallocate memory. TC++PL 19.4.

alignment

placing objects in memory to suit hardware requirements. On many machines, an object must be aligned on a word boundary for acceptable performance.

this

pointer to the object for which a non-static member function is called. TC++PL 10.2.7, D&E 2.5.2.

void*

pointer to void; that is, a pointer to an object of unknown type; also called pointer to raw memory. A void* cannot be used or assigned without a cast. TC++PL 5.6, D&E 11.2.1, 11.2.3.

data abstraction

programming relying on user-defined types with well-defined interfaces. See also: generic programming and object-oriented programming. TC++PL 2.5, 24.2.2, D&E 9.2.1.

ANSI C

see C.

Koenig lookup

see argument-based lookup.

field

see bitfield.

hierarchy

see class hierarchy.

block

see compound statement. See also: try-block.

concept checking

see constraint.

template argument constraint

see constraint.

member data

see data member.

subtype

see derived class. See also: public base.

protection

see encapsulation.

backslash

see escape character.

handler

see exception handler

inlining

see inline function.

I/O

see iostream

input

see iostream.

output

see iostream.

stream

see iostream.

stream I/O

see iostream.

extension

see language extension

nested function

see local function.

nested class

see member class.

out_of_range

standard exception thrown by vector if an argument to at() is out of range. TC++PL 16.3.3.

bad_cast

standard exception thrown if a dynamic_cast to a reference fails. TC++PL 15.4.1.1, D&E 14.2.2.

cin

standard istream. TC++PL 3.6, 21.3.1 D&E 8.3.1.

sort()

standard library algorithm for sorting a random access sequence, such as a vector or an array. Example comparing sort() to qsort(). TC++PL 18.7.1.

set

standard library associative container

auto_ptr

standard library class template for representing ownership of an object in a way that guarantees proper release (delete) even when an exception is thrown. See also: resource management, resource acquisition is initialization. TC++PL 14.4.2.

complex

standard library complex number template parameterized by scalar type. TC++PL 11.3, 22.5, D&E 3.6.1, 8.5, 15.10.2.1.

queue

standard library first-in-first-out sequence. TC++PL 17.3.2.

find()

standard library linear search algorithm for a value in a sequence. TC++PL 18.5.2.

find_if()

standard library linear search algorithm for an element meeting a search criterion in a sequence. TC++PL 18.5.2.

list

standard library linked container. See also: vector, map. TC++PL 3.7.3, 17.2.2.

valarray

standard library numeric vector type supporting vector operations. TC++PL 22.4.

priority_queue

standard library queue where a priority determines the order in which an element reaches the head of the queue. TC++PL 17.3.3.

vector

standard library template providing contiguous storage, re-sizing and the useful push_back() functions for adding elements at the end. Vector is the default container. See also: map, multimap, list, deque. TC++PL 3.7.1, 16.3.

cout

standard ostream. TC++PL 3.4, 21.2.1, D&E 8.3.1.

cerr

standard unbuffered ostream for error or diagnostic output. TC++PL 21.2.1.

string

standard-library type representing a sequence of characters, support by convenient operators, such as == and +=. The general form of of strings, basic_string, supports strings of different kinds of characters. TC++PL 3.5, 20.

most-derived type

the type used to create an object (before any conversions). See also: dynamic type, static type.

POD

"Plain Old Data" - (roughly) a class that doesn't contain data members that would be illegal in C. A POD can therefore be used for data that needs to be share with C functions. A POD can have non-virtual member functions.

RTFM

"Read The Manual" (The 'F' is silent). Usually a very good idea.

glossary

"collection of glosses; lists and explanations of special words." - The Advanced Learners Dictionary of Current English. A pain to compile.

object

(1) a contiguous region of memory holding a value of some type. (2) a named or unnamed variable of some type; an object of a type with a constructor is not considered an object before the constructor has completed and is no longer considered an object once a destructor has started executing for it. Objects can be allocated in static memory, on the stack, on on the free store. TC++PL 4.9.6, 10.4, 10.4.3, D&E 2.3, 3.9.

general-purpose programming language

(1) a programming language intended for use in a wide range of application areas without restrictions that make it totally unsuitable for traditional major uses of computers, such as mathematical computations, data processing, text processing, graphics, and communications. (2) a language that can do what at least as much as other languages called "general purpose" can do. See also: C++.

C/C++

(1) an abbreviation used when discussing similarities, differences, and compatibility issues of C and C++. (2) a mythical language referred to by people who cannot or do not want to recognize the magnitude of differences between the facilities offered by C and C++ or the significant differences in the programming styles supported by the two language. See also: multi-paradigm programming, object-oriented programming, generic programming, exception, template, user-defined type, C++ standard library.

typename

(1) an alternative to "class" when declaring template arguments; for example, "template<typename T> void f(T);" (2) a way of telling a compiler that a name is meant to name a type in template code; for example "template<class T> void f(T a) { typename T::diff_type x = 0; ... }". TC++PL C::13.5.

inserter

(1) an iostream << (put to) function. (2) an STL operation yielding an iterator to be used for adding elements to a containter. TC++PL 19.2.4, 21.2, D&E 8.3.1. See also: extracter, back_inserter, front_inserter.

explicit qualification

(1) by namespace name, see qualified name. (2) by template argument. TCP++L 13.3.2.

language extension

(1) relatively new feature that people haven't yet gotten used to. (2) proposed new feature. (3) feature provided by one or more implementations, but not adopted by the standard; the use of some such features implies lock-in to a particular compiler supplier.

interface function

A function that can access the representation of a class. See also: friend, member function, derived class, protected.

resource acquisition is initialization

A simple technique for handling resources in programs using exceptions. One of the keys to exception safety. Example. TC++PL 14.4, E.3 D&E 16.5.

Stepanov

Alex Stepanov is the original designer and implementer of the STL. D&E 11.15.2.

return type relaxation

Allowing a virtual function returning a B* or a B& to be overridden by a function with a return type D* or D&, provided B is a public base of D. See also: overriding. TC++PL 15.6.2, D&E 13.7.

ACCU

Association of C and C++ Users. A users group that among other things maintains a collection of professional book reviews.

TC++PL

Bjarne Stroustrup: The C++ Programming Language (Special Edition). Addison Wesley. 2000.

D&E

Bjarne Stroustrup: The Design and Evolution of C++. Addison Wesley. 1994. A book describing why C++ looks the way it does - the closest to a design rationale that we have for C++.

Borland C++ Builder

Borland's implementation of C++ together with proprietary libraries for Windows programming in an IDE.

Kernighan

Brian Kernighan is a co-author of Kernighan & Ritchie: "The C programming Language".

K&R C

C as defined by Kernighan and Ritchie.

malloc()

C standard allocation function. Use new or vector instead.

realloc()

C standard allocation function. Use vector and push_back() instead.

function prototype

C term for a function declaration that isn't also a function definition. D&E 2.6.

ANSI C++

C++

Standard C++

C++ as defined by ISO.

C/C++ compatibility

C++ was designed to be as compatible as possible to C, but no more. This basically means as compatible as can be without compromising C++'s level of type safety. You can download Appendix B of TC++PL,. Compatibility, which describes incompatibilities and differences in facilities offered by C and C++. TC++PL B. D&E 2.7, 3.12, 4.5.

ISO C++

C++.

nullptr

C++0x keyword for the null pointer. It is not an integer. It can be assigned only to pointers.

decltype

C++ox operator meaning the type of its operand. For example: const double& d1 =2.0; decltype(d1) d2; (d2 will also be a const double&). Primarily useful for writing forwarding functions in generic programming.

user-defined type

Class or enumeration. A programmer can define meanings for operators for user-defined types. See also: operator overloading. TC++PL 6.2, 11, D&E 3.6, 11.7.1.

uncaught exception

Exception for which no handler was found. Invokes terminate(), which by default terminates the program. TC++PL 14.7.

GUI

Graphical User Interface. There are many C++ libraries and tools for building GUI-based applications, but no standard C++ GUI.

14882

ISO/IEC 14882 - Standard for the C++ Programming Language.

terminate()

If an exception is thrown but no handler is found, terminate() is called. By default, terminate() terminates the program. If program termination is unacceptable, a user can provide an alternative terminate() function. If you are worried about uncaught exceptions, make the body of main() a try-block. TC++PL 14.7.

auto

In C and C++98 a largely useless keyword redundantly indicating stack allocation for local variables. In C++0x a keyword indicating that a variable gets its type from its initializer. For example: double d1 = 2; auto d2 = 3*d1; (d2 will have type double). Primarily useful in generic programming.

resumption semantics

In some languages, but not C++, an exception handler can respond by telling the thrower to resume (``just carry on as if the problem hadn't happened"). This looks like a good idea in some cases, but in general leads to contorted code because of unfortunate dependencies between separate levels of abstraction. See also: termination semantics. TC++PL 14.4.5, D&E 16.6.

IDE

Integrated (or Interactive) Development Enviornment. A software development environment (SDE) emphasizing a GUI interface centered around a source code editor. There are many IDEs for C++, but no standard SDE.

Visual C++

Microsoft's implementation of C++ together with proprietary libraries for Windows programming in an IDE.

NCITS

National Committee for Information Technology Standards. The part of ANSI that deals with programming language standards, notably C++, and sells copies of the C++ standard. Formerly known as X3.

explicit call of constructor

See placement new.

SDE

Software Development Environment. An environment of editors, compilers, tools, libraries, etc. used by a programmer to produce software. There are many SDEs for C++, but no standard SDE.

C89

The 1989 ANSI standard for C based on K&R C with a few additions borrowed from C++, such as function prototypes and const. See also: K&R C, C99.

C99

The 1999 ISO standard for C based on C89 with additions to support Fortran-style numeric computation. It also borrows a few more features, such as line comments (// comments) and declarations as statements, from C++.

ANSI

The American national standards organization. Cooperates closely with ISO over the C++ standard.

ARM

The Annotated C++ Reference Manual by Margaret Ellis and Bjarne Stroustrup. The 1990 C++ reference manual with detailed comments about design details and implementation techniques. Now outdated. See also: C++ standard.

standard library

The library defined in the C++ standard. Contains strings, stream I/O, a framework of containers and algorithms, support for numerical computation, support for internationalization, the C standard library, and some language support facilities. See also: complex, valarray, locale. TC++PL 16-22, D, E.

argument passing

The semantics of function call is to pass a copy of an argument. The copy operation is defined by the argument type's copy constructor or by binding to a reference. In either case the semantics is those of initialization. TC++PL 7.2.

history of C++

The work on what became C++ started by Bjarne Stroustrup in AT&T Bell Labs in 1979. The first commercial release was in 1985. Standards work stared in 1990 leading to ratification of the ISO standard in 1998. TC++PL 1.4. D&E Part 1.

new_handler

a (possibly user-defined) function called by new if operator new() fails to allocate sufficient memory. See also: std::bad_alloc exception. TC++PL 6.2.6.2, 14.4.5., 19.4.5.

concept

a C++ language construct, providing type chaecking for template arguments.

strcmp()

a C-style standard library function for comparing C-style strings.

private base

a base class declared private in a derived class, so that the base's public members are accessible only from that derived class. TC++PL 15.3.2, D&E 2.10.

protected base

a base class declared protected in a derived class, so that the base's public and protected members are accessible only in that derived class and classes derived from that. TC++PL 15.3.2, D&E 13.9.

virtual base

a base that is shared by all classes in a class hierarchy that has declared it virtual. TC++PL 15.2.4, D&E 12.3, 12.4.1.

try-block

a block, prefixed by the keyword try, specifying handlers for exceptions. See also: catch, exception handling. TC++PL 8.3.1,14.3, D&E 16.3.

integral type

a bool, character type, or integer type. Supports arithmetic and logical operations. TC++PL 4.1.1.

type

a built-in type or a user-defined type. A type defines the proper use of a name or an expression. TC++PL 2.3.1, 4.1.

downcast

a cast from a base class to one of its derived classes. The name reflects the fact that in programming, trees tend to be drawn growing downwards from the roots. See also: dynamic_cast, upcast, crosscast. TC++PL 15.4.

upcast

a cast from a derived class to one of its bases. See also: downcast, crosscast. TC++PL 15.4.

exception handler

a catch-clause associated with a try-block for handling exceptions of a specified type. TC++PL 8.3.1, 14.3, D&E 16.3-4.

abstract class

a class defining an interface only; used as a base class. Declaring a member function pure virtual makes its class abstract and prevents creation of objects of the abstract class. Use of abstract classes is one of the most effective ways of minimizing the impact of changes in a C++ program and for minimizing compilation time. Example. TC++PL 2.5.4, 12.4.2, D&E 13.2.

base class

a class from which another is derived. TC++PL 2.6.2, 12, 15, D&E 2.9.

order of construction

a class object is constructed from the bottom up: first bases in declaration order, then members in declaration order, and finally the body of the constructor itself. TC++PL 10.4.6, 12.2.2, 15.2.4.1, 15.4.3. D&E 2.11.1, 13.2.4.2.

order of destruction

a class object is destroyed in the reverse order of construction. See also: destructor.

specialization

a class or function generated from a template by supplying a complete set of template arguments. TC++PL 13.2.2, 13.5, D&E 15.10.3.

facet

a class representing a primitive aspect of a locale, such as a way of writing an integer or a character encoding. TC++PL D.3.

member class

a class that is a member of another; also called a nested class. TC++PL 11.12, D&E 3.12, 13.5.

sequence adapter

a class that provides a modified interface to another. For example, a standard library stack is an adapter for a more flexible data structure such as a vector. See also: adapter, stack, queue, priority_queue. TC++PL 17.3.

adapter

a class that takes arguments producing a function object that performs an operation based on those arguments. A simple form of a higher-order function. For example, mem_fun() adapts a member function for use by the standard algorithms. See also: sequence adapter. TC++PL 18.4.4.

Hungarian notation

a coding convention that encodes type information in variable names. Its main use is to compensate for lack of type checking in weakly-typed or untyped languages. It is totally unsutable for C++ where it complicates maintenance and gets in the way of abstraction.

class hierarchy

a collection of classes organized into a directed acyclic graph (DAG) by derived/base relationships. TC++PL 2.6.2, 12, 15, D&E 1.1, 7.2, 8.2.3.

boost.org

a collection of people - many with ties to the C++ standards committee - devoted to creating a body of quality - peer reviewed - open source libraries designed to interoperate with the standard library. Their central "home" is their website.

application

a collection of programs seen as serving a common purpose (usually providing a common interface to their users).

invariant

a condition of the representation of an object (the object's state) that should hold each time an interface function is called; usually established by a constructor TC++PL 24.3.7, E.3.5.

virtual constructor

a constructor cannot be virtual, because to create an object, we need complete information of its type. "virtual constructor" is the name of a technique for calling a virtual function to create an object of an appropriate type. Example. TC++PL 12.4.4, 15.6.2.

definition

a declaration that specifies the entity to which the declared name refers. See also: one definition rule, variable definition, const definition, template definition, function definition. TC++PL 4.9, D&E 15.11.3.

inheritance

a derived class is said to inherit the members of its base classes. TC++PL 2.6.2, 12.2, 23.4.3.1, D&E 3.5, 7.2, 12.

subclass

a derived class.

virtual destructor

a destructor declared virtual to ensure that the proper derived class destructor is called if an object of a derived class is deleted through a pointer to a base class. If a class has any virtual functions, it should have a virtual destructor. Example. TC++PL 12.4.2, D&E 10.5.

#define

a directive that defines a macro.

Comeau C++

a family of ports of the EDG C++ front-end.

fstream

a file stream for input and output.

floating-point type

a float, double, or long double. A floating-point number is typically represented as a mantissa and an exponent. TC++PL 4.5.

recursion

a function calling itself, hopefully with different arguments so that the recursion eventually ends with a call for which the function doesn't call itself. See also: iteration. TC++PL 7.1.1.

friend function

a function declared as friend in a class so that it has the same access as the class' members without having to be within the scope of the class. And, no, friends do not "violate encapsulation". TC++PL 11.5, 11.2.3, C.11.4, D&E 2.10, 3.6.1.

member function

a function declared in the scope of a class. A member function that is not a static member function must be called for an object of its class. TC++PL 10.2.1, D&E 2.3, 3.5.

friend

a function or class explicitly granted access to members of a class by that class. TC++PL 11.5, C.11.4, D&E 2.10, 3.6.1-2.

binder

a function taking a function and a value, returning a function object; when called, that function object will invoke the function with the value as an argument in addition to other arguments supplied in the call. The standard library provides bind1st() and bind2nd() for binding the first and second argument of a binary function, respectively. TC++PL 18.4.4.

free-standing function

a function that is not a member function. Useful for decreasing coupling between representation and algorithm. TC++PL 7, 18.

clone

a function that makes a copy of an object; usually a clone function relies on run-time information (e.g. a virtual function call) to correctly copy an object given only a pointer or reference to a sub-object.

C++

a general-purpose programming language with a bias towards systems programming that supports procedural programming, data abstraction, object-oriented programming, and generic programming. C++ was designed and originally implemented by Bjarne Stroustrup. C++ is defined by ISO/IEC 14882 - Standard for the C++ Programming Language. TC++PL describes C++ and the fundamental techniques for its use. A description of the design considerations for C++ can be found in D&E. Many commercial and free implementations exist. TC++PL 1.3,-5, 2.1, D&E 0.

void

a keyword used to indicate an absence of information. TC++PL 4.1.1, 4.7.

extern

a keyword used to indicate that the definition of an entity being declared is defined elsewhere. Because "extern: is only necessary for global variables it is largely redundant.

finally

a language construct supporting ad hoc cleanup in some languages. Similar, but not identical to C++'s catch(...). Use the "resource acquisition is initialization" technique instead.

while-statement

a loop statement presenting its condition "at the top". For example, while (cin>>var) vec.push_back(var);

#include

a mechanism for textual inclusion of one source file into another. Typically used to compose a translation unit out of a .c file and the header files it needs to define its view if the rest of the program. TC++PL 2.7, 13, D&E 18.1.

protected member

a member accessible only from classes derived from its class. TC++PL 15.3.1, D&E 13.9.

private member

a member accessible only from its own class. TC++PL 2.5.2, 10.2.2, 15.3, D&E 2.10.

public member

a member accessible to all users of a class. TC++PL 2.5.2, 10.2.2, 15.3, D&E 2.10.

virtual member function

a member function that a derived class can override; the primary mechanism for run-time polymorphism in C++. A virtual member function is sometimes called a method. See also: overriding, pure virtual function. TC++PL 2.5.4, 2.5.5, 12.2.6, D&E 3.5, 12.4.

static member function

a member function that need not be called for an object of the class. TC++PL 10.2.4, D&E 13.4.

address

a memory location. TC++PL 5.1.

enumerator

a name identifying a value of an enumeration. TC++PL 4.8, D&E 11.7.

namespace

a named scope. TC++PL 2.5.1, 8.1, C.10. D&E 17.

function

a named sequence of statements that can be invoked/called given arguments and that might return a value. The type of the function includes the number and types of argument and the type of the value returned, if any. See also: function declaration, function body. TC++PL 2.3, 7, D&E 2.6.

bitfield

a number of bits in a word made accessible as a struct member. TC++PL C.8.1

word

a number of bytes that on a given machine is particularly suied to holding an integers or a pointer. On many machines, an object must be aligned on a word boundary for acceptable performance. An int is typically a stored in a word. Often, a word is 4 bytes. See also: alignment. TC++PL 4.6.

template parameter

a parameter of a template.

optimizer

a part of a compiler that eliminates redundant operations from code and adjusts code to perform better on a given computer. See also, front-end, back-end, code generator. D&E 3.3.3.

catch-clause

a part of a try-block that handles exceptions of a specified type. Also called a handler or an exception handler. TC++PL 8.3.1, 14.3, D&E 16.3-4.

suffix operator

a postfix operator.

algorithm

a precise definition of a computation. The standard library provides about 60 standard algorithms, such as sort(), search(), and copy_unique(). TC++PL 3.8, 18.

object-oriented programming language

a programming language designed to support or enforce some notion of object-oriented programming. C++ supports OOP and other effective forms of programming, but does not try to enforce a single style of programming. See also: generic programming, multi-paradigm programming, hybrid language.

EDG C++ front-end

a quality C++ compiler front-end, which is the core of several well-regarded C++ compilers.

scope

a region of source text delimited by curly braces: { ... }, a list of function or template parameters, or all of a translation unit outside other scopes. See also: block, namespace, global scope. TC++PL 2.9.4.

file

a sequence of bytes or words holding information in a computer. The term "file" is usually reserved to information placed on disk or elsewhere outside the main memory. The iostream part of the C++ standard library provides ifstream, ofstream, and fstream as abstraction for accessing files. TC++PL 21.5.

interface

a set of declarations that defines how a part of a program can be accessed. The public members and the friends of a class defines that class' interface for other code to use. A class without data members defines a pure interface. The protected members provide an additional interface for use by members of derived classes. See also: abstract class.

character set

a set of integer values with a mapping to character representations; for example, ASCII (ANSI13.4-1968) gives meaning to the values 0-127. ASCII is C++'s representation character set, the character set used to represent program source text. TC++PL C.3. D&E 6.5.3.

overload resolution

a set of rules for selecting the best version of an operator based on the types of its operands. A set of rules for selecting the best version of an overloaded function based on the types of its arguments. The intent of the overload resolution rules is to reject ambiguous uses and to select the simplest function or operator for each use. TC++PL 6.2, D&E 11.2.

program

a set of translation units complete enough to be made executable by a linker. TC++PL 9.4.

integer type

a short, int, or long. Standard C++ doesn't support long long. TC++PL 4.4.

handle class

a small class that provides interface to an object of another class. A handle is the standard way of providing variable sized data structures in C++. Examples are string and vector. TC++PL 25.7.

trait

a small policy object, typically used to describe aspects of a type. For example, iterator_trait specifies the types resulting from operations on an iterator T. TC++PL 19.2.2.

two-phase lookup

a somewhat complicated mechanism used in compilation of templates. Names that do not depend on a template parameter are looked up (and bound) early, i.e., when the template template definition is first seen ("phase 1 lookup"). Names that depend on a template parameter are looked up late, i.e. during template instantiation ("phase 2 lookup") so that the lookup can find names relating to actual template arguments. TC++PL C::13.8.

termination semantics

a somewhat ominous terminology for the idea that throwing an exception "terminates" an operation and returns through the function call chain to a handler. The handler can initiate any error handling it likes, including calling the function that caused the exception again (presumably after fixing the problem that caused the problem). What a handler can't do is simply tell the thrower to just carry on; by the time the handler is invoked we have returned from the block/function that threw and all blocks/functions that led to it from the handler's try-block. See also: resumption semantics. TC++PL 14.4.5, D&E 16.6.

istringstream

a string stream for input.

ostringstream

a string stream for output.

union

a struct with all members allocated at the same offset within an object. The language does not guarantee type safety for all uses of unions. Primarily used to save space. TC++PL C.8.2.

grammar

a systematic description of the syntax of a language. The C++ grammar is large and rather messy. Some of the syntactic complexity was inherited from C. TC++PL A, D&E 2.8.

double dispatch

a technique for selecting a function to be invoked on the dynamic type of two operands. TC++PL 21.2.3.1, D&E 13.8.

partial specialization

a template used (only) for the subset of its template parameters that matches a specialization pattern. TC++PL 13.5.

const_cast

a type conversion operation that conversion between types that differ in const and volatile type modifiers only. See also: cast. TC++PL 15.4.2.1, D&E 14.3.4.

static_cast

a type conversion operation that converts between related types, such as pointer types within a class hierarchy and between enumerations and integral types. See also: cast, dynamic_cast. TC++PL 6.2.7, 15.4.2.1, D&E 14.3.2.

dynamic_cast

a type conversion operation that performs safe conversions using on run time type information. Used for navigation of a class hierarchy. See also: downcast, crosscast, static_cast. TC++PL 15.4.1, D&E 14.2.2, 14.3.2.1.

reinterpret_cast

a type conversion operation that reinterprets the raw memory of an object as a value of another type. The result of a reinterpret_cast can only be portably used after being converted back into its original type. Use only as a last resort. See also: cast. TC++PL 6.2.7, D&E 14.3.3.

default template argument

a type or value specified for an argument in a template declaration, to be used if a use of the template doesn't provide a type or value for that argument. This is commonly used to allow a simple interface for common uses while making it easy to use less common facilities by specifying more arguments. See also: default argument. TC++PL 13.4.1, B.3.5.

concrete type

a type without virtual functions, so that objects of the type can be allocated on the stack and manipulated directly (without a need to use pointers or references to allow the possibility for derived classes). Often, small self-contained classes. See also abstract class, vector, list, string, complex. TC++PL 25.2.

prefix operator

a unary operato that appears before its operand. For example, &var.

postfix operator

a unary operator that appears after its operand. For example var++.

bit

a unit of memory that can hold 0 or 1. An individual bit cannot be directly accessed in C++ (the unit of addressing is a byte), but a bit can be accessed through a bitfield or by using the bitwise logical operators & and |. TC++PL 6.2.4.

byte

a unit of memory that can hold a character of the C++ representation character set. The smallest unit of memory that can be directly addressed in C++. Usually, a byte is 8 bits. TC++PL 4.6.

user-defined type conversion

a user can define conversions either as constructors or conversion operators. These conversions are applied explicitly or implicitly just like built-in conversions. TC++PL 11.3.5, 11.4, D&E 3.6.1, 3.6.3.

class

a user-defined type. A class can have member functions, member data, member constants, and member types. A class is thee primary mechanism for representing concepts in C++. See also: template class. TC++PL 2.5.2, 10, D&E 2.3.

argument

a value passed to a function or a template. In the case of templates, an argument is often a type.

default argument

a value specified for an argument in a function declaration, to be used if a call of the function doesn't specify a value for that argument. This is commonly used to allow a simple interface for common uses while making it easy to use less common facilities by specifying more arguments. See also: default template argument, binder. TC++PL 7.5, 10.2.3, D&E 2.12.2.

parameter

a variable declared in a function or templates for representing an argument. Also called a formal argument. Similarly, for templates.

controlled variable

a variable used to express the part of the exit condition of a loop that varies each time around the loop. For example ``i'' in for (int i=0; i<max; ++i) f(i);

placement new

a version of the new operator where the user can add arguments to guide allocation. The simplest form, where the object is placed in a specific location, is supported by the standard library. Example. For example, placement new is used in the implementation of standard library containers. See also: explicit call of destructor. TC++PL 10.4.11, E.3.1, D&E 10.4.

multi-method

a virtual function that selects the function to be called based on more than one operand. See also: multiple dispatch. D&E 13.8.

memory management

a way of allocating and freeing memory. In C++ memory is either static, allocated on the stack, or allocated on the free store. When people talk about memory management, they usually think of free store or even specifically about garbage collection. Memory can often be effectively managed through standard library containers, such as vector or string, or through general resource management techniques. See also: auto_ptr, constructor, destructor, resource acquisition is initialization. TC++PL C.9, D&E 3.9, 10.

visitor pattern

a way of using double dispatch to simulate virtual calls without adding new virtual functions.

protected

access control keyword. See protected member, protected base.

public

access control keyword. See public member, public base.

access control

access to bases and members of a class can be controlled by declaring them public, protected, or private. TC++PL 15.3, D&E 2.3, 13.9.

+=

add-and-assign operator; a+=b is roughly equivalent to a=a+b. Often a useful operation for user-defined types. TC++PL 6.1.1, 6.2, 11,3,2, 20.3.9, 22.5.

operator new()

allocation function used by new. Possibly defined by user. TC++PL 6.2.6.2, 19.4.5. See also: operator delete().

operator new[]()

allocation function used by new. Possibly defined by user. TC++PL 6.2.6.2, 19.4.5. See also: operator delete[]().

namespace alias

alternative name for a namespace; often a shorter name. TC++PL 8.2.7, D&E 17.4.3.

digraph

alternative representation for C++ representation characters that doesn't exist in every national character set, such as {, }, [, ], and #: <%, %., <:, :>, and %:. TC++PL C.3.1.

trigraph

alternative representation for C++ representation characters that doesn't exist in every national character set, such as {, }, [, ], and #: ??<, ??>, ??(, ??), and ??=. TC++PL C.3.1.

mem_fun()

an adapter that allows a member function to be used as an argument to a standard algorithm requiring a free-standing function. TC++PL 18.4.4.2.

reference

an alternative name for an object or a function. See also: operator overloading, call-by-reference. TC++PL 5.4.1, D&E 3.7.

function argument

an argument to a function.

template argument

an argument to a template.

undefined

an aspect of C++'s semantics for which no reasonable behavior is required. An example is dereferencing a pointer with the value zero. Avoid undefined behavior. See also: implementation defined. TC++PL C.2.

implementation defined

an aspect of C++'s semantics that is defined for each implementation rather than specified in the standard for every implementation. An example is the size of an int (which must be at least 16 bits but can be longer). Avoid implementation defined behavior whenever possible. See also: undefined. TC++PL C.2.

copy assignment

an assignment accepting an object of the class itself as its argument, typically Z::operator=(const Z&). A copy assignment is used for assignment of an object of type T with an object of type T. If a copy assignment is not declared for a class, memberwise copy is used. See also: copy constructor. TC++PL 10.4.4.1, 10.4.6.3 D&E 11.4.

ofstream

an file stream for output.

fat interface

an interface with more member functions and friends than are logically necessary. TC++PL 24.4.3.

declaration

an introduction of a name into a scope. The type of the name must be specified. If the declaration also specifies the entity to which the name refers, the declaration is also a definition. TC++PL 4.9, D&E 3.11.5.

extracter

an iostream >> (put to) function. TC++PL 21.2,21.3, D&E 8.3.1.

pointer

an object holding an address or 0. TC++PL 2.3.3, 5.1, D&E 9.2.2.1, 11.4.4.

element

an object in a container.

copying class object

an object of a class is copied by the class' copy assignment and copy constructors. The default meaning of these operations is memberwise copy. TC++PL 10.4.4.1, 10.4.6.3 D&E 11.4.

handle

an object that controls access to another. Often, a handle also controls the acquisition and release of resources. A common use is for a handle to control access to a variably-sized data structure. See also: resource acquisition is initialization, vector, string, smart pointer. TC++PL 25.7, D&E 11.5.2.

policy object

an object used to specify guide decisions (e.g. the meaning of "less than") or implementation details (e.g. how to access memory) for an object or an algorithm. See also trait, facet. TC++PL 13.4, 24.4.1.

unary operator

an operator taking one operand, such as ! and unary *.

ternary operator

an operator taking three operands, such as ?:.

binary operator

an operator taking two operands, such as /, &&, and binary *.

BCPL

ancestor to C and C++ designed and implemented by Martin Richards. TC++PL 1.4, D&E 1.1, 3.1.

resource

any entity that a program acquires and releases. Typical examples are free store, file handles, threads, sockets. See also: resource acquisition is initialization, exception safety, basic guarantee, resource management. TC++PL 14.4, E.2-3 D&E 16.5.

extended type information

any scheme that provides additional information base on the standard run time type information. TC++PL 15.4.4.1, D&E 14.2.5.2.

programming language

artificial language for expressing concepts and general algorithms in a way that lends itself to solving problems using computers. There do not appear to be a general consensus on what a programming language is or should be. TC++PL 1.3.2, 2.1-2, D&E page 7.

volatile

attribute of a declaration telling the compiler that an entity can have its value changed by extralinguistic means; for example, a real time clock: "extern volatile const long clock;". Limits optimizations. TC++PL A.7.1.

int

basic signed integer type; its precision is implementation-defined, but an int has at least 32 bits. TC++PL 2.3.1, 4.4.

comment

block comment /* ... */ or line comment // ...

false

bool value; converts to 0. TC++PL 4.2, D&E 11.7.2.

true

bool value; converts to 1. TC++PL 4.2, D&E 11.7.2.

catch(...)

catch every exception. TC++PL 14.3.2, D&E 16.5.

character type

char, unsigned char, and signed char. These are three distinct types. See also: wchar_t. TC++PL 2.3.1, 4.3, C.3.4.

char

character type; typically an 8-bit byte. See also: wchar_t. TC++PL 4.3, C.3.4.

whitespace

characters that a represented only by the space they take up on a page or screen. The most common examples are space (' '), newline ('\n'), and tab ('\t').

type_info

class containing basic run time type information. TC++PL 15.4.4, D&E 14.2.5.1.

local class

class defined within a function. Most often, the use of a local class is a sign that a function is too large. Beware that a local class cannot be a valid template argument.

template

class or function parameterized by a set of types, values, or templates. See also template instantiation, specialization, template class, template function. TC++PL 2.7, 13, D&E 15.

template class

class parameterized by types, values, or templates. The template arguments necessary to identify the class to be generated for the class template must be provided where a template class is used. For example "vector<int> v;" generates a vector of ints from the vector template. See also template. TC++PL 13.2, D&E 15.3.

struct

class with members public by default. Most often used for data structures without member functions or class invariants, as in C-style programming. TC++PL 5.7, 10.2.8, D&E 3.5.1.

bug

colloquial term for error.

expression

combination of operators and names producing a value. TC++PL 6.2.

initializer list

comma-separated list of expressions enclosed in curly braces, e.g. { 1, 2, 3 } used to initialize a struct or an array. TC++PL 5.2.1, 5.7, 11.3.3.

block comment

comment started by /* and terminated by */. TC++PL 6.4, D&E 3.11.1.

line comment

comment started by // and terminated by end-of-line. TC++PL 6.4, D&E 3.11.1.

member constant

const or enumeration declared as a member. If initialized in-class, such a constant can be used in constant expressions within the class. TC++PL 10.4.6.2.

default constructor

constructor requiring no arguments. Used for default initialization. TC++PL 10.4.2, 10.4.6, D&E 2.12.2, 15.11.3.

explicit constructor

constructor so that will not be used for implicit conversions. TC++PL 11.7.1.

array

contiguous sequence of elements. An array doesn't know its own size; the programmer must take care to avoid range errors. Where possible use the standard library vector. TC++PL 5.2-3, C.7.

operator

conventional notation for built-in operation, such as +, *, and &. A programmer can define meanings for operators for user-defined types. See also: operator overloading, unary operator, binary operator, ternary operator, prefix operator, postfix operator. TC++PL 6.2.

implicit type conversion

conversion applied implicitly based on an expected type and the type of a value. See also, explicit type conversion, user-defined type conversion. TC++PL 11.3.3, 11.3.5, 11.4, C.6, D&E 2.6.2, 3.6.1, 3.6.3, 11.2.

memberwise copy

copying a class object by copying each of its members in turn, using proper copy constructors or copy assignments. That's the default meaning of copy. TC++PL 10.4.4.1, 10.4.6.3, D&E 11.4.4.

design

creating a clean and reasonably simple structure of a system TC++PL 23.3.

=0

curious notation indicating that a virtual function is a pure virtual function. TC++PL 12.3. D&E 13.2.1.

global data

data defined in the global scope. This is usually best avoided because a programmer can't easily know what code manipulates it and how. It is therefore a common source of errors. Global constants are usually ok.

operator delete()

deallocation function used by delete#. Possibly defined by user. TC++PL 6.2.6.2, 19.4.5. See also: operator new().

operator delete[]()

deallocation function used by delete#. Possibly defined by user. TC++PL 6.2.6.2, 19.4.5. See also: operator new[]().

const definition

declaration of a const including an initializer.

function declaration

declaration of a function, including its name, argument types, and return type.

using-declaration

declaration of a local synonym for a name in another namespace or class. Example of using-declaration used to simplify overloading. See also: overloading, argument-based lookup. TC++PL 8.2.2. D&E 17.4.

template definition

declaration of a template class or of a template function including a function body.

call-by-reference

declaring a function argument type to be a reference, thus passing a reference rather than a value to the called function. See Also: call-by-value. TC++PL 5.5, D&E 3.7.

overriding

declaring a function in a derived class with the same name and a matching type as a virtual function in a base class. The argument types must match exactly. The return types must match exactly or be co-variant. The overriding function will be invoked when the virtual function is called. TC++PL 15.6.2, 6.2, D&E 3.5.2-3, 13.7.

hybrid language

derogative term for a programming language that supports more programming styles (paradigms) rather than just object-oriented programming.

Liskov Substitution Principle

design classes so that any derived class will be acceptable where its base class is. C++ public bases enforce that as far as the interface provided by the base class. TC++PL 24.3.4, D&E 2.10.

multi-paradigm design

design focussed on applying the various paradigms to their best advantage. See also: multi-paradigm programming.

object-oriented design

design focussed on objects and object-oriented programming. TC++PL 23.2, D&E 7.2.

explicit call of destructor

destructors are implicitly called when an object goes out of scope or is deleted. However, if a user have taken over construction (using placement new) and destruction, a destructor must be explicitly called. Example. For example, explicit call of destructor is used in the implementation of standard library containers. See also: placement new. TC++PL 10.4.11, E.3.1, D&E 10.5.1.

using-directive

directive making a namespace accessible. See also: argument-based lookup. TC++PL 8.2.3. D&E 17.4.

deque

double-ended queue (pronounced "deck"). A standard library template alowing insertions and deletions at both ends. Use a vector if you need insertions and deletions only at one end (as is typical). Use a list if you need frequent insertions and deletions in the middle. TC++PL 17.2.3.

new-style cast

dynamic_cast, static_cast, const_cast, or reinterpret_cast. D&E 14.3.

explicit instantiation

explicit request to instantiate a template in a specific context. See also: template instantiation. TC++PL C.13.10, D&E 15.10.1.

conversion

explicit type conversion or implicit type conversion. See also: user-defined type conversion.

constant expression

expression of integral type that is evaluated at compile time. TC++PL C.5.

long double

extended-precision floating-point number. TC++PL 4.5.

macro

facility for character substitution; doesn't obey C++ scope or type rules. C++ provides alternatives to most uses of macros; see template, inline, const, and namespace. Don't use macros unless you absolutely have to. TC++PL 7.8, D&E 2.9.2, 4.4, 18.

.c file

file containing definitions.

header file

file holding declarations used in more than one translation unit. Thus, a header file acts as an interface between separately compiled parts of a program. A header file often contains inline function definitions, const definitions, enumerations, and template definitions, but it cannot be #included from for than one source file if it contain non-inline function definitions or variable definitions. TC++PL 2.4.1, 9.2.1. D&E 2.5, 11.3.3.

learning C++

focus on concepts and techniques. You don't need to learn C first. See also "Learning Standard C++ as a New Language", available from my papers page. How do I start?. TC++PL 1.2, 1.7, D&E 7.2.

iteration-statement

for-statement, while-statement, or do-statement.

function definition

function declaration including a function body.

local function

function defined within a function. Not supported by C++. Most often, the use of a local function is a sign that a function is too large.

operator function

function defining one of the standard operators; e.g. operator+(). See also: operator, operator overloading, conversion operator.

random number generator

function or function object producing a series of pseudorandom numbers according to some distribution. TC++PL 22.7.

template function

function parameterized by types, values, or templates. The function to be generated from a template function can usually be deduced from the function arguments in a call. For example, "sort(b,e)" generates "sort<vector::iterator>(b,e)" from the sort() template function if b and e are standard library vector iterators. If a template argument cannot be deduced, it must be provided through explicit qualification. See also template. TC++PL 13,3, D&E 15.6.

higher-order function

functions that produce other functions. C++ does not have general higher-order functions, but by returning function objects a function can efficiently emulate some techniques traditionally relying of higher-order functions. See also: binder. TC++PL 18.4.4.

initialization

giving an object an initial value. Initialization differs from assignment in that there is no previous value involved. Initialization is done by constructors.

overloading

having more than one function with the same name in the same scope or having more than one operator with the same name in the same scope. It is not possible to overload across different scopes. See also: using-declaration. TC++PL 6.2, D&E 3.6, 11.2.

operator overloading

having more than one operator with the same name in the same scope. Built-in operators, such as + and *, are overloaded for types such as int and float. Users can define their own additional meanings for user-defined types. It is not possible to define new operators or to give new meanings to operators for built-in types. The compiler picks the operator to be used based on argument types based overload resolution rules. See also: overload resolution. TC++PL 6.2, D&E 3.6, 11.7.1.

standard header

header for standard library facility. Included using the "#include< ... >" syntax. TC++PL 9.2.2, 16.1.2.

selection-statement

if-statement or switch-statement. TC++PL 6.3.2.

run time type information

information about a type available at run time through operations on an object of that type. See also: dynamic_cast, typeid(), and type_info. TC++PL 15.4, D&E 14.2.

base initializer

initializer for a base class specified in the constructor for a derived class. TC++PL 12.2.2, 15.2.4.1, D&E 12.9.

member initializer

initializer for a member specified in the constructor for its class. TC++PL 10.4.6, 12.2.2, D&E 12.9.

istream

input stream type. TC++PL 3.6, 21.3.

long int

integer of a size greater than or equal to the size of an int. TC++PL 4.4.

short

integer of a size less than or equal to the size of an int. TC++PL 4.4.

reverse iterator

iterator for iterating through a sequence in reverse order. TC++PL 19.2.5.

enum

keyword for declaring enumerations. TC++PL 4.8, D&E 11.7.

virtual

keyword used to declare a member function virtual.

explicit

keyword used to define a constructor so that it isn't used for implicit conversions. TC++PL 11.7.1.

catch

keyword used to introduce a catch-clause.

try

keyword used to start a try-block.

proprietary language

language owned by an organization that is not an official standards organization, such as ISO; usually manipulated by its owner for commercial advantage.

modifiable lvalue

lvalue that is not const. TC++PL 4.9.6.

multimap

map that allows multiple values for a key. TC++PL 17.4.2.

member type

member class, member enumeration, or member typedef.

const member function

member function declared not to modify the state of the object for which it is called. Can be called for const objects only. TC++PL 10.2.6, D&E 13.3.

push_back()

member function that adds an element at the end of a standard container, such as vector, thereby increasing the container's size by one. Example. TC++PL 3.7.3, 16.3.5, E.3.4.

constructor

member function with the same name as its class, used to initialize objects of its class. Often used to establish an invariant for the class. Often used to acquire resources. A constructor establishes a local environment in which member functions execute. See also: order of construction, destructor. TC++PL 10.2.3, D&E 2.11.1.

data member

member of a class that can hold a value. A memer can be a static member or a non-static member. TC++PL 2.5.2-3, 10.2, D&E 2.3, 2.5.2.

free store

memory allocated by new; also called dynamic memory. Often standard library facilities, such as vector, can be used to avoid explicit use of free store. TC++PL 6.2.6, 10.4.3, D&E 2.11.2, 11.4.2.

uninitialized memory

memory that hasn't been initialized to hold a specific value of a type. TC++PL 19.4.4.

C++03

name for the minor revision of the C++ standard represented by the 2003 corrigenda ("a bug fix release").

variable

named object in a scope. TC++PL 2.3.1, 10.4.3, D&E 2.3.

literal

notation for values of bool, character types, integer types, or floating-point types. See also: enumerators. TC++PL 4.2, 4.3.1, 4.4.1, 4.5.1, 5.2.2, D&E 11.2.1.

new

object creation operator. See also: constructor, placement new, operator new(), resource management, memory management, garbage collection. TC++PL 6.2.6, 19.4.5, D&E 2.3, 10.2.

delete

object destruction operator. Invokes destructor, if any. See also: resource management, memory management, garbage collection, operator delete(). TC++PL 6.2.6, D&E 2.3, 10.2.

closure

object representing a context. C++ does not have general closures, but function objects can be efficiently used to hold specific parts of a context relevant to a computation. TC++PL 22.4.7, 18.4.

exception

object thrown by a throw-statement and (potentially) caught by an exception handler associated by a try-block. See also: exception safety, termination semantics, catch. TC++PL 8.3, 14.2, D&E 16.

function object

object with the application operator, operator()(), defined so that it can be called like a function. A function object is more general than a function because it can hold data and provide additional operations. Sometimes called a functor. Given current compiler technology, simple function objects inline better than pointers to functions, so that parameterization with function objects can be far more efficient than use of pointers to functions or virtual functions. See also: binder, adapter, inlining. Example. TC++PL 18.4.

throw

operation for interrupting the normal flow of control and returning to an appropriate exception handler identifyed by the type of the exception throw. See also: catch, exception handling. TC++PL 8.3.1, 14.3, D&E 16.3.

prohibiting operations

operations can be rendered inaccessible by declaring them private; in this way default operations, such as construction, destruction, and copying can be disallowed for a class. TC++PL 11.2.2, D&E 11.4.

cast

operator for explicit type conversion; most often best avoided. See also dynamic_cast, C-style cast, new-style cast. TC++PL 6.2.7, D&E 7.2, 14.2.2.1.

conversion operator

operator function specifying a conversion from a user-defined type to either another user-defined type or a built-in type. Note that constructors cannot define conversions to built-in types. TC++PL 11.4, D&E 3.6.3.

typeid()

operator returning basic type information. TC++PL 15.4.4, D&E 14.2.5.

sizeof

operator yielding the size of an object.

ostream

output stream type. TC++PL 3.4, 21.2.

call-by-value

passing a copy of an argument to the called function. The semantics of function call is to pass a copy of an argument. The copy operation is defined by the argument type's copy constructor. See Also: call-by-reference. TC++PL 7.2.

information hiding

placing information where it can be accessed only through a well-defined interface. See also: access control, abstract class, separate compilation. TC++PL 2.4.

char*

pointer to a char or an array of char. Typically assumed to point to a C-style string. Prefer a standard library string over a C-style string when you can. TC++PL 2.3.3, 13.5.2.

paradigm

pretentious and overused term for a way of thinking. Often used with the erroneous assumption that "paradigms" are mutually exclusive, and often assuming that one paradigm is inherently superior to all others. Derived from Kuhn's theory of science. TC++PL 2.2.

Currying

producing a function of N-M arguments by specifying M arguments for a function of N arguments. See also: binder, default argument. TC++PL 18.4.4.1.

type conversion

producing a value of one type from a value of another type. A type conversion can be an implicit conversion or an explicit conversion. See also: user-defined type conversion, cast. TC++PL 6.2.7.

multi-paradigm programming

programming applying different styles of programming, such as object-oriented programming and generic programming where they are most appropriate. In particular, programming using combinations of different programming styles (paradigms) to express code more clearly than is possible using only one style. See also: C++.

resource leak

programming error causing a resource not to be released. See also: resource acquisition is initialization, basic guarantee. TC++PL 14.4, E.2-3 D&E 16.5.

pure object-oriented language

programming language claiming to support only object-oriented programming. C++ is designed to support several programming paradigms, including traditional C-style programming, data abstraction, object-oriented programming, and generic programming. For a longer explanation, read Why C++ isn't just an object-oriented programming language. See also: hybrid language.

C

programming language designed and originally implemented by Dennis Ritchie. C++ is based on C and maintains a high degree of compatibility with C. See also: K&R C, C89, C99, ANSI C. TC++PL B, D&E 3.12.

object-oriented programming

programming using class hierarchies and virtual functions to allow manipulation of objects of a variety of types through well-defined interfaces and allow a program to be extended incrementally through derivation. See also: polymorphism, data abstraction. TC++PL 2.6, 12, D&E 3.5, 7.2.

procedural programming

programming using procedures (functions) and data structures (structs). See also: data abstraction, object-oriented programming, generic programming, multi-paradigm programming. TC++PL 2.3.

generic programming

programming using templates to express algorithms and data structures parameterized by data types, operations, and polices. See also: polymorphism, multi-paradigm programming. TC++PL 2.7, 24.4.1, D&E 15.11.2.

polymorphism

providing a single interface to entities of different types. virtual functions provide dynamic (run-time) polymorphism through an interface provided by a base class. Overloaded functions and templates provide static (compile-time) polymorphism. TC++PL 12.2.6, 13.6.1, D&E 2.9.

back_inserter()

returns an iterator that can be used to add elements at the back of a container. TC++PL 19.2.4.

front_inserter()

returns an iterator that can be used to add elements at the front of the container . TC++PL 19.2.4.

constraint

rule that restricts the set of acceptable arguments for a template parameter. For example "the argument must have + and - operators". Examples. D&E 15.4.

inequality operator

see !=.

include

see #include.

.cpp file

see .c file

.cxx file

see .c file

put function

see <<.

assignment operator

see =.

equality operator

see ==.

get function

see >>.

Bell labs

see AT&T Bell Labs.

Stroustrup

see Bjarne Stroustrup.

C++ standards process

see C++ standards committees

standards committee

see C++ standards committees.

old-style cast

see C-style cast.

ISO C

see C.

compatibility

see C/C++ compatibility.

design of C++

see D&E.

G++

see GNU C++.

Classic C

see K&R C.

LSP

see Liskov Substitution Principle.

zero

see NULL

RTTI

see Run Time Type Information.

Microsoft C++

see Visual C++

interface inheritance

see abstract class, public base.

abstract type

see abstract class.

error handling

see exception handling.

dynamic memory

see free store.

functor

see function object.

procedure

see function.

automatic garbage collection

see garbage collection.

header

see header file

.h file

see header file.

data hiding

see information hiding

hiding

see information hiding

function member

see member function.

identifier

see name.

object code

see object file.

OOD

see object-oriented design.

OOPL

see object-oriented programming language.

OOP

see object-oriented programming.

ODR

see one definition rule

overloaded operator

see operator overloading

overload

see overloading.

overloaded function

see overloading.

override

see overriding.

cpp

see preprocessor.

implementation inheritance

see private base.

RAII

see resource acquisition is initialization.

co-variant return type

see return type relaxation.

separately compiled

see separate compilation.

class template

see template class.

function template

see template function.

instantiation

see template instantiation.

self

see this.

raw memory

see uninitialized memory.

using

see using-directive and using-declaration.

method

see virtual member function.

vptr

see virtual-function pointer.

vtbl

see virtual-function table.

name

sequence of letters and digits started by a letter, used to identify ("name") user-defined entities in program text. An underscore is considered a letter. Names are case sensitive. The standard imposes no upper limit on the length of names. TC++PL 4.9.3.

compound statement

sequence of statements enclosed in curly braces: { ... } See also: try-block. TC++PL 2.3, 6.3.

float

single-precision floating-point number. TC++PL 4.5.

copy()

standard algorithm for copying one sequence into another. The two sequences need not be of the same type. TC++PL 18.6.1.

bad_alloc

standard exception thrown by new in case of failure to allocate free store. TC++PL 6.2.6.2, 19.4.5.

map

standard library associative container, based on "less than" ordering. See also: hash_map, vector, list. TC++PL 3.7.4, 17.4.1.

locale

standard library class for representing culture dependencies relating to input and output, such as floating-point output formats, character sets, and collating rules. A locale is a container of facets. TC++PL 21.1, D.

switch-statement

statement selecting among many alternatives based on an integer value. TC++PL 6.3.2.

if-statement

statement selecting between two alternatives based on a condition. TC++PL 6.3.2.

memory

static memory, stack, or free store.

file stream

stream attached to a file. See also, fstream, ifstream, ofstream. TC++PL 21.5.1.

string stream

stream attached to a string. See also, stringstream, istringstream, ostringstream. TC++PL 21.5.3.

not

synonym for !, the logical negation operator TC++PL C.3.1.

and

synonym for &&, the logical and operator. TC++PL C.3.1.

bitand

synonym for &, the bitwise and operator. TC++PL C.3.1.

xor

synonym for ^, the bitwise exclusive or operator TC++PL C.3.1.

typedef

synonym for some type declared using the keyword typedef.

bitor

synonym for |, the bitwise or operator TC++PL C.3.1.

or

synonym for ||, the logical or operator TC++PL C.3.1.

regression testing

systematically checking that a new version of a program doesn't break correct uses of a previous version of the program.

testing

systematically verifying that a program meets its specification and systematically searching for error.

virtual-function table

table of all virtual functions for a class. The most common way of implementing virtual functions is to have each object of a class with virtual functions contain a virtual function pointer pointing to the class' virtual function table.

Library TR

technical report from the ISO C++ standards committee defining a set of new standard library components, including regular expression matching (regexp), hashedcontainers (ordered_map), and smart pointers. See my C++ page.

Performance TR

technical report from the ISO C++ standards committee discussing issues related to perfoemance, especially as concerns embedded systems programming and hardware access. See my C++ page.

delayed evaluation

technique for eliminating temporary values, and in general to delay a computation until sufficient information is available to do it well. TC++PL 21.4.6.3, 22.4.7.

garbage collection

techniques for reclaiming unused memory without relying on user-supplied delete or free() commands. A permitted but not required technique for C++. Commercial and free garbage collectors exist for C++: See my C++ page. Use of classes that control their own storage, such as the standard library vector, string, and map, reduces the need for garbage collection. See also: resource acquisition is initialization, destructor. TC++PL C.9.1. D&E 10.7.

STL

the "Standard Template Library" by Alex Stepanov, which became the basis for the containers, algorithms, and iterators part of the ISO C++ standard library. TC++PL 15-19.

C++98

the ISO C++ standard. See my C++ page.

C++ standards committees

the ISO committee for C++ (WG21) and the various national standards committees that closely cooperate with it (BIS, AFNOR, DIN, etc.). Did the ANSI/ISO standards committee spoil C++?. See also: C++ Standard. D&E 6.2.

abstraction

the act of specifying a general interface hiding implementation details. Classes, abstract classes, and templates are the primary abstraction mechanisms in C++. See also: encapsulation.

=

the assignment operator; not an equality operator. = can be used for non-const built-in types (except arrays), enumerations, strings, containers, iterators, complex, and valarray. For a class, = is by default defined member-wise assignment; if necessary, the writer of a class can define it differently. TC++PL 2.3.1, 6.2, 11.2, 16.3.4, 20.3.6, 22.4.3, 22.5, D&E 2.12.1,11.4.4.

statement

the basic unit controlling the execution flow in a function, such as if-statement, while-statement, do-statement, switch-statement, expression statement, and declaration. TC++PL 6.3.

value

the bits of an object interpreted according to the objects type.

bool

the built-in Boolean type. A bool can have the values true and false. TC++PL 4.2, D&E 11.7.2.

escape character

the character \, also called backslash, sed an initial character in representations of characters that cannot be represented by a single ASCII character, such as newline ('\n') and horizontal tab ('\t'). TC++PL C.3.2.

C++ standard

the definition of C++ provided by ISO. Available from ANSI; see my C++ page. TC++PL 1.4, B.1. D&E 6.1.

Bjarne Stroustrup

the designer and original implementor of C++. The author of this glossary. See also: my home page.

encapsulation

the enforcement of abstraction by mechanisms that prevent access to implementation details of an object or a group of objects except through a well-defined interface. C++ enforces encapsulation of private and proteced members of a class as long as users do not violate the type system using casts. See also: interface and access control. TC++PL 15.3, 24.3.7.4, D&E 2.10.

==

the equality operator; compares values for equality returning a bool. == can be used for built-in types, enumerations, strings, iterators, complex, and valarray. == is not by default defined for a class, but a user can define it for a user-defined type. Note that == doesn't have the naively expected meaning for C-style strings or arrays. TC++PL 2.3.1, 6.2, 16.3.10, 20.3.8, 22.4.3, 22.5.

Cfront

the front-end of Bjarne Stroustrup's original C++ compiler. D&E 3.3.

main()

the function called by the system to start a C++ program. TC++PL 3.2, 6.1.7, 9.4 .

multiple dispatch

the generalization of double dispatch to more operands. See also: single dispatch.

strong guarantee

the guarantee that an exception thrown by an operation leaves every object in the state in which it was before the start of the operation. Builds on the basic guarantee. See also exception safety, nothrow guarantee, and basic guarantee. TC++PL E.2.

nothrow guarantee

the guarantee that an operation will not throw an exception. See also exception safety, basic guarantee, and strong guarantee. TC++PL E.2.

basic guarantee

the guarantee that basic invariants are maintained if an exception is thrown and that no resources are leaked/lost. Provided by all standard library operations. See also exception safety, nothrow guarantee, and strong guarantee. TC++PL E.2.

AT&T Bell Labs.

the industrial research and development labs where C and C++ were invented, initially developed, and initially used. D&E 2.14.

!=

the inequality operator; compares values for inequality returning a bool. TC++PL 2.3.1, 6.2, 16.3.10, 20.3.8, 22.4.3, 22.5.

goto

the infamous goto. Primarily useful in machine generated C++ code. TC++PL 6.3.4.

ISO

the international standards organization. It defines and maintains the standards of the major non-proprietary programming languages, notably C++.

C standard library

the library defined for C in the C standard. Inherited by C++. Most C standard library functions have safer and more convenient alternatived in the C++ standard library. See also: algorithm, container, stream I/O, string, locale.

protection model

the mechanisms for access control. See public, private, protected, friend. TC++PL 15.3, D&E 2.10.

exception safety

the notion that a program is structured so that throwing an exception doesn't cause unintended side effects. See also: basic guarantee, strong guarantee, and nothrow guarantee. You can download Appendix E Standard-Library Exception Safety of TC++PL describing techniques for exception handling. TC++PL E.2.

size of an object

the number of bytes required to represent an object. See also sizeof, alignment. TC++PL 4.6.

function body

the outermost block of a function. See also: try-block, function definition. TC++PL 2.7, 13.

linker

the part of a C++ implementation that merge the code generated from separately compiled translation units into a program or part of a program. TC++PL 9.1, D&E 4.5, 11.3.

compiler

the part of a C++ implementation that produces object code from a translation unit. See also: front-end, back-end.

preprocessor

the part of a C++ implementation that removes comments, performs macro substitution and #includes. Avoid using the preprocessor whenever possible. See also: macro, #include, inline, const, template, namespace. TC++PL 7.8, 9.2.1, D&E 18.

code generator

the part of a compiler that takes the output from the front-end and generates code from it. See also: back-end, optimizer.

back-end

the parts of a compiler that generates code given an internal representation of a correct program. This representation is produced by a compiler front-end. See also: front-end.

front-end

the parts of a compiler that perform lexical and syntax checking, type checking, and initial semantic checking of a translation unit. Typically all compiler error messages comes from the front-end. See also: back-end. D&E 3.3.

separate compilation

the practice of compiling parts of a program, called translation units, separately and then later linking the results together using a linker. This is essential for larger programs. See also: linkage, header file, one definition rule. TC++PL 2.4.1, 9.1. D&E 2.5.

exception handling

the primary way of reporting an error that cannot be handled locally. An exception is thrown and will be caught by an exception handler or terminate() will be called. See also: exception safety, termination semantics, try-block, throw, catch. TC++PL 8.3, 14, E, D&E 16.

type checking

the process of checking that every expression is used according to its type. the compiler checks every expression based on the declared types of the names involved. TC++PL 7.2-3, 24.2.3, D&E 2.3, 2.6, 3.10, 3.15, 9.2.2.1.

template instantiation

the process of creating a specialization from a template. TC++PL 13.2.2, D&E 15.10.

linkage

the process of merging code from separately compiled translation units into a program or part of a program. TC++PL 9.

type safety

the property that an object can be accessed only according to its definition. C++ approximates this ideal. A programmer can violate type safety by explicitly using a cast, by using an uninitialized variable, by using a pointer that doesn't point to an object, by accessing beyond the end of an array, and by misusing a union. For low-level systems code, it can be necessary to violate type safety (e.g. to write out the byte representation of some objects), but generally type safety must be preserved for a program to be correct and maintainable.

object file

the result of compiling a source file. See also: compiler.

executable file

the result of linking the object files of a complete program. See also: compiler, linker.

semantics

the rules specifying the meaning of a syntactically correct construct of a program. For example, specifying the actions taken to perform a for-statement or an object definition.

global scope

the scope containing all names defined outside any function, class, or namespace. Names in the global scope can be prefixed by ::. For example, ::main(). TC++PL 2.9.4.

syntax

the set of gramatical rules specifying how the text of a program must be composed. For example, specifying the form of a declaration or the form of a for-statement.

signature

the set of parameter types for a function; that is, the function's type ignoring its return type. This is a confusingly specialized definition compared to other programming languages where "signature" means "function type".

type system

the set of rules for how objects can be used according to their types. See also: type checking.

floating-point literal

the source text representation of a floating point value. For example, 0.314e1. TC++PL 4.5.1.

single dispatch

the technique of choosing the member function to be invoked based on the object used in the call. See also: double dispatch.

dynamic type

the type of an object as determined at run-time; e.g. using dynamic_cast or typeid. Also known as most-derived type.

static type

the type of an object as known to the compiler based on its declaration. See also: dynamic type.

C++0x

the upcoming revision of the ISO C++ standard; 'x' is scheduled to be '9'. See my publicatons page.

multiple inheritance

the use of more than one immediate base class for a derived class. One typical use is to have one base define an interface and another providing help for the implementation. TC++PL 12.2.4, 12.4, 15.2.5, D&E 12.

one definition rule

there must be exactly one definition of each entity in a program. If more than one definition appears, say because of replication through header files, the meaning of all such duplicates must be identical. TC++PL 9.2.3, D&E 2.5, 15.10.2.

iteration

traversal of data structure, directly or indirectly using an iteration-statement. See also: recursion. The standard library offer algorithms, such as copy() and find(), that can be effective alternatives to explicit iteration. TC++PL 6.3.3. 18.

function try-block

try-block associated with the outmost block of a function, the function body. TC++PL 3.7.2.

sibling class

two classes are siblings if a class is (directly or indirectly) derived from them both and one is not derived from the other. Note that this is a rather inclusive definition of "sibling class" in that is does not require that the siblings have the same immediate derived class (I didn't want to introduce a notion of "cousin classes"). See also: dynamic_cast, crosscast.

explicit type conversion

type conversion (explicitly) requested by the use of a C-style cast, new-style cast, or functional notation. See also, implicit type conversion, user-defined type conversion. TC++PL 6.2.7, D&E 14.3.2.

dynamic type safety

type safety enforced at run time (typically requiring a programmer to catch exceptions to deal with violations). An example is range checking for vectors.

static type safety

type safety enforced before a program starts executing (at compile time or at static link time).

incomplete type

type that allows an object to be copied, but not otherwise used. A pointer to an undeclared type is the typical example of an incomplete type.

member

type, variable, constant, or function declared in the scope of a class. TC++PL 5.7, 10.2, D&E 2.3, 2.5.2, 2.11.

smart pointer

user-defined type providing operators like a function, such as * and ++, and with a semantics similar to pointers. See also: iterator. Sometimes smart a pointer is called a handle. TC++PL 11.10-11, 13.6.3.1, 19.3, 25.7, D&E 11.5.1

default value

value defined by a default constructor. For built-in types, the default value is defined to be 0. TC++PL 4.9.5, 10.3.1, 10.4.2 D&E 15.11.3.

static variable

variable allocated in static memory. TC++PL 7.1.2, 10.2.4, 10.4.3, D&E 3.9.

pure virtual function

virtual function that must be overridden in a derived class. Indicated by the curious =0 syntax. A pure virtual function can be defined in the class where it is declared pure, but needn't be and usually isn't. A class with at least one pure virtual function is an abstract class. TC++PL 12.3. D&E 13.2.1.

wchar_t

wide character type. Used to hold characters of character sets that require more than a byte to represent, such as unicode. TC++PL 4.3, C.3.3. See also: large character sets, universal character name.

maintenance

work on a program after its initial release. Typical maintenance activities include bug fixing, minor feature enhancements, porting to new systems, improvements of error handling, modification to use different natural languages, improvements to documentation, and performance tuning. Maintenance typically consumes more than 80% of the total effort and cost expended on a program.

C-style string

zero-terminated array of characters, supported by C standard library functions. A low-level and error-prone mechanism; where possible prefer strings. TC++PL 3.5.1, 20.3.7, 20.4.

NULL

zero. 0. 0 is an integer. 0 can be implicitly converted to every pointer type. See also: nullptr. TC++PL 5.1.1, D&E 11.2.3.