Defining New Datatypes

ByWalter Wimberly

OK, defining a new Datatype might be a bit of a stretch…how about, defining aliases?

You can use the typedef keyword to define a new aliase for an existing data type in C++. The general form is:

typedef existingType newType;

Let’s say you have experience with another language and you want to use a datatype name that they had. Or you want to simplify the unsigned sub-type, well typedef lets you do that.

typedef int integer; // now you can say integer x instead of int x;
typedef int* intp; // or integer pointer if you prefer

So why would you do something like that? Well, as you might imagine, it’s easy to forget to use a * when defining a variable. It’s not only easy to forget, it’s easy to overlook because it’s a single character and the datatype is right. This should help reduce confusion when writing code,and reducing confusion means less errors and less frustration.

Just a friendly little tip.

Defining New Datatypes was originally found on Access 2 Learn

Assistant Professor

Walter Wimberly is an Assistant Professor at a regional college in Tennessee, teaching Computer Science in the Software Engineering track. He works as a student advisor, oversees curriculum changes, develops new courses, and manages the advisory panel.
Walter taught full time for about 7 years, before going back into “industry” as a full stack Software Developer for a dozen years. There he focused on web based projects coding in JavaScript/jQuery and utilizing the Bootstrap CSS Framework on the front-end, and coding in PHP, ASP/ASP.Net, SQL on the back-end.

Since he loves teaching, he taught as an adjunct web and digital media classes for eight (8) years, while working in industry, and has since returned to teaching full time.

He has been married for over 25 years, and is father to several special needs boys. As such, he is working on some projects to help others who have special needs to be self-sufficient, and support the care givers of those with special needs. Check out his Autism blog for more info.

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