10.3: Typedef - An Alias
- Page ID
- 10298
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General Discussion
The typedef statement allows the programmer to create an alias, or synonym, for an existing data type. This can be useful in documenting a program. The C++ programming language syntax is:
typedef <the real data type> <the alias identifier name>;
Let's say a programmer is using a double data type to store the amount of money that is being used for various purposes in a program. He might define the variables as follows:
Regular Definition of Variables double income; double rent; double vacation;
However, he might use the typedef statement and define the variables as follows:
Using typedef when Defining Variables typedef double cash; the typedef must be defined before its use cash income; cash rent; cash vacation;
The typedef statement is not used very often by beginning programmers. It usually creates more confusion than needed, thus stick to using the normal data types at first.
Definitions
- typedef
- Allows the programmer to create an alias, or synonym, for an existing data type.