C++ Identifiers

C++ Identifiers

All C++ variables must be identified with unique names.

These unique names are called identifiers.

Identifiers can be short names (like x and y) or more descriptive names (age, sum, totalVolume).

Note: It is recommended to use descriptive names in order to create understandable and maintainable code:

Example

The general rules for constructing names for variables (unique identifiers) are:

• Names can contain letters, digits and underscores
• Names must begin with a letter or an underscore (_)
• Names are case sensitive (myVar and myvar are different variables)
• Names cannot contain whitespaces or special characters like !, #, %, etc.
• Reserved words (like C++ keywords, such as int) cannot be used as names

Practice Excercise Practice now

C++ Constants

When you do not want others (or yourself) to override existing variable values, use the const keyword (this will declare the variable as "constant", which means unchangeable and read-only):

Example

You should always declare the variable as constant when you have values that are unlikely to change:

Example

 

Practice Excercise Practice now