Tokens

Tokens

The  Collection of a valided character set in “C” is called token.

Types of Tokens

·         Keyword

·         Identity

·         Constant

·         String constant

·         Operation

Example:

·         Keyword :- It is predefine word in the library we cannot change it during the programming.

                Eg:- int, float, char, long, double, switch, case, break, auto, else, if, for etc.

·         Identifiers :- It can define as a programmer define element like the name of variables, function, arrays. Rules for naming the identifiers :-

1 .  An identifiers is any combination of alphabetic digit or underscore.

Eg:- int a@ (*)  int a# (*)

2 . The first character In the identifier name must be an alphabet.

               

3 . No, comma or blanks space are allowed with an identifier.

4 . Length of the identifier depend upon complier.

5 . No special symbol other that under score can used.

6 . Upper case & lower case are dishing.

7 . A keyword cannot be used as a identifier.

8 . Identifier should be unique. Same identifier name cannot repeated with in a scope.

·         Constant :- It can be categorized in two types. It value doesn’t change during the programming.

 Type of Constant :-

1 . Literal constant :-   Directly used constant value is called literal constant.

2 . Symbolic constant :- Rether than using direct value we can created symbol to the literal constant by using # define directive before main () is called symbolic constant