Why should i prototype a function

The output of the below kinds of programs is generally asked at many places. Take a step-up from those "Hello World" programs.

Learn to implement data structures like Heap, Stacks, Linked List and many more! Check out our Data Structures in C course to start learning today. Next Static functions in C. Recommended Articles. It states that function area takes two arguments of type int and returns area of type int. The only difference between the function definition and its function prototype is the addition semicolon ; at the end of prototype declaration. But, the parameter identifier could be different in function prototype and function definition because the scope of parameter identifier in a function prototype is limited within the prototype declaration.

Actually, the compiler ignores the name of the parameter list in the function prototype. Having said that, it is good programming practice to include parameter names which increase program clarity. If you do so, C checks the types and counts of all parameter lists. Try compiling the following:. Place one prototype for each function at the beginning of your program. They can save you a great deal of debugging time, and they also solve the problem you get when you compile with functions that you use before they are declared.

For example, the following code will not compile:. Why, you might ask, will it compile when add returns an int but not when it returns a float? Because older C compilers default to an int return value.

Using a prototype will solve this problem. By closing this banner, scrolling this page, clicking a link or continuing to browse otherwise, you agree to our Privacy Policy. Popular Course in this category. Course Price View Course. Free Software Development Course. Login details for this Free course will be emailed to you. Email ID. Contact No.