Re: [Mysqlcppapi-main] testing result data for null

[Jonathan W. <co...@co...>]

On Tue, May 17, 2005 at 12:24:14PM -0700, Julian Pellico wrote:

> Hi,

Hi Julian,

> How can I determine whether a ColData item is null across versions of
> this library?

I'm afraid a macro might be the only way.

> The test in the old version I was using was is_null(), but in a newer
> version it's ism_bNull(). I would prefer to write code that can be
> linked against either of these versions...

(Are you using the released packages on sourceforge.net or CVS?)

I'm not a big fan of the naming convention used in ColData, although I
don't like the old names either.

For the record:

     version 1.7             version 1.9
GET: bool is_null() const -> bool ism_bNull() const
SET: void it_is_null()    -> void is_null()

I don't like ism_bNull() at all, since it uses the name of a private
variable in the public interface. This exposes implementation detail and
makes the name of the function hard to remember unless you know the
implementation.


I would prefer to use is_null() for both getting and setting the value:

     version 1.7             version 1.9         version 2.0
GET: bool is_null() const -> bool ism_bNull() -> bool is_null()
SET: void it_is_null()    -> void is_null()   -> void is_null(bool)

is_null() with no argument queries the value and is_null() with argument
modifies it.

Unfortunately, I don't think it will be possible to switch between
a new version and 1.7 and be link-compatible.

jon