On Tue, Jul 12, 2011 at 8:29 AM, Albert ARIBAUD albert.u.boot@aribaud.netwrote:
Hi Anton,
Le 11/07/2011 18:19, Anton Staaf a écrit :
I know that this is throwing more fuel on the fire (for which I am sorry),
but I don't follow the argument that this is unportable. As far as I can tell, the # : # syntax is not using any special compiler extensions, it is simply substituted into a (boo) ? # : # expression, thus extracting either the first of second number from the definition of the bit field.
If I am wrong I would be interested to know what about this is not standard pre-processor usage?
For me at least (Wolfgang might have other reasons), the issue is not the use of the pre-processor per se, it is that this "syntax" breaks the '?:' "triadic" operator in pieces, one piece in argument value and one in macro body, and neither piece makes sense from a C standpoint: '5:3' represents no meaningful C entity, and 'X ? y' (without the ':' and third argument of the operator) is not a proper C construct.
Yes, this is absolutely true, and we can argue about readability vs. usability vs. maintainability of such a construct (I like it, but I realize that I might be in a minority here). But it is certainly portable, there is nothing compiler or pre-processor specific here. I just wanted to clarify that so that we could have the correct debate. :)
IOW, it is syntactic sugaring done at the expense of code readability.
I would disagree here, it is indeed syntactic sugar, but I would assert that it is done exactly to make the code more readable. The one piece of macro magic is in a single file that can be well documented and encapsulated. I find having one #define that specifies the entire range much easier to read and debug than having two #defines, one for each end of the range that you have to make sure are matched. And this simplification can be applied to many many files. But that's what it really boils down to, what we each find easier to read and debug. I'm fine if the decision is that everyone else doesn't like the way this reads, but let's not throw it out based on a compatibility argument that is invalid.
Thanks, Anton
Thanks,
AntonAmicalement,
Albert.