[pkmays]

I'm not C++ savvy, but I know from reading Google's C++ style guide that they also disable exceptions. The guide leaves it at that and doesn't say anything more about how to deal with errors. Does anyone here know how these big Google C++ codebases handle errors instead?

[andyjohnson0]

[The following is speculation: I have no access to Google's code.]

I can't think of any other way to handle errors apart from using return values. Methods return error codes which are handled by the caller or bubbled-up to its caller. This tends to result in lots of duplicated error handling code, and you have to either dedicate the return value to success/fail (which means you have to return non-status data some other way) or use special values to indicate failure.

The Go language (from Google) doesn't have exceptions and allows functions to return a value and an additional error return value [1]. I'd guess that this is inspired by their approach to C++ coding.

[1] http://code.google.com/p/go-wiki/wiki/Errors

[rb12345]

Isn't it possible to fake this with C++ templates? As an example, I created https://github.com/rb12345/cpp_annotated_return, which uses a templated struct to allow multiple value returns.

[andyjohnson0]

Yes, you could do it that way. Personally I'd restrict the error code to always be an int, which makes for a terser syntax as you don't need the second template parameter.

You could also extend it to support multiple non-error return values, like Python does. But this introduces problems with expressing the contract between caller and called (e.g. [1]) and I think the best way to address this might be to extend the language syntax.

I think one of the most interesting design choices in Go is that it intentionally omits conventional exceptions. It does have defer/panic/recover [2] though.

[1] http://stackoverflow.com/questions/354883/how-do-you-return-... [2] http://blog.golang.org/2010/08/defer-panic-and-recover.html