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Getting a result from a function

There are two mechanisms in C++ for getting a result back from a function. These are:

• the function return value
• a reference parameter

These mechanisms are independent of each other. They can be used together in the same functions (for example, a function that returns one result using the function return value and passing another result through a reference parameter). But in many cases it is best to avoid mixing these mechanisms in one function. So for now I would recommend that you follow these suggestions:

• If a function has no results to "return", use a void function.
• If a function has one result to "return", you have a choice. You can use a value-returning function and use the return statement to return the result. Or you can use a void function with a reference parameter to pass the result back.
• If a function has multiple results to "return", use a void function with a reference parameter for each result.

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