Re: What value and type should my functions return?

From:

Jeff Schwab <jeff@schwabcenter.com>

Newsgroups:

comp.lang.c++

Date:

Thu, 05 Mar 2009 20:48:21 -0500

Message-ID:

<doadnZ0p9NxtHS3UnZ2dnUVZ_tudnZ2d@giganews.com>

dwightarmyofchampions@hotmail.com wrote:

Hello. I am currently learning the C++ language, and I'm having
trouble with functions. Generally speaking, should my functions be
returning bool, void, or int?

There's no "generally speaking" here. The appropriate return type
varies wildly from one function to the next.

And how is my main function supposed to
handle errors in my function definitions?

By catching exceptions.

#include <cstdlib>
#include <iostream>
#include <stdexcept>

double divide(double dividend, double divisor) {
     if (divisor == 0.0) {
         throw std::range_error( "attempted division by zero" );
     }
     return dividend / divisor;
}

int main() try {
     std::cout << "3.0 / 5.0 == " << divide(3.0, 5.0) << '\n';
     std::cout << "3.0 / 0.0 == " << divide(3.0, 0.0) << '\n';
     return EXIT_SUCCESS;
} catch (std::exception const& x) {
     std::cerr << "error: " << x.what() << '\n';
     return EXIT_FAILURE;
}

As an example, suppose I have a function foo() return true if the
function had no errors and false if an error was encountered

That's common in C, but it's usually the wrong thing to do in C++.