RE: [boost] Re: Runtime error reporting

From: scleary_at_[hidden]
Date: 2001-03-20 17:43:37

> IMO this sort of API cries out for exceptions.
> 
> void foo ()
> {
>   try {
>      put_text(TextString);
>  }
>  catch (TextErrors &terr)
>  {
>    // do something useful here with terr.
>  }
>  // let unknown errors percolate up the stack.

Agreed; exceptions are better for unforseeable run-time errors; asserts are
more suited for double-checking invariants.  I've tried several different
Win32 API return value checking methods, and the one that I settled on is
simply:
  if (!EmptyClipboard())
    Win32_error::raise("CloseClipboard");
where Win32_error is a class I've defined whose static member function
"raise" will throw an exception of that type.

Unexpected errors are propogated up the stack, and at the topmost level (in
WinMain), I just have a catch for std::exception which prints the message as
a fatal error and (cleanly) shuts down.

My prefered style is more verbose than some, but I prefer this over the
  Win32Check(EmptyClipboard());
style (or BOOST_CHECK or whatever you want) because I wanted a better error
message (like letting me know what Win32 function had the error -- also can
pass context information and the error code as optional parameters), but
without the run-time overhead if the error didn't occur.

        -Steve