Page 27 - DCAP404 _Object Oriented Programming

Object-oriented Programming

Notes
Table 2.1: C++ Keywords
asm double new switch
auto else operator template
break enum private this
case extern protected throw
catch float public try
char for register typedet
class friend return union
const goto short unsigned
continue if signed virtual
default inline sizeof void
delete int static volatile
do long struct while

2.1.2 Identifiers

Identifiers refer to the names of variables, functions, arrays, classes, etc., created by the
programmer. They are the fundamental requirement of any language. Each language has its
own rules for naming these identifiers. The following rules are common to both C and C++:
1. Only alphabetic characters, digits and underscores are permitted.
2. The name cannot start with a digit.

3. Uppercase and lowercase letters are distinct.
4. A declared keyword cannot be used as a variable name.
A major difference between C and C++ is the limit on the length of a name. While ANSI C
recognizes only the first 32 characters in a name, C++ places no limit on its length and, therefore,
all the characters in a name are significant.
Care should be exercised while naming a variable that is being shared by more than one file
containing C and C++ programs. Some operating systems impose a restriction on the length of
such a variable name.

!
Caution The first character in an identifier must be a letter or the _ (underscore) character;
however, beginning identifiers with an underscore is considered poor programming
style.

Self Assessment

Fill in the blanks:
1. The keywords not found in ANSI C are shown …………………. .

2. A major difference between C and C++ is the limit on the length of a………………. .

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