On 9/27/2013 7:18 PM, "Luís Marques" <[email protected]>" wrote:
My point here is not to argue against your choice for the
standard library. My issues of version(X, Y) arose in client code
(non-lib), where it seems to me that the second kind of bug is
probably more likely to occur than the first kind. So, I politely
ask, are you sure the language should not support something like
version(X, Y), for cases where developers think that it is a
better trade-off than multiple version() blocks?
I understand your point and reasoning, and it has come up repeatedly.
It's not obvious why, but that feature (in C and C++) leads to wretched,
unmaintainable, buggy, coding horrors. You don't have to take my word for it -
do a grep for #if across some C or C++ code that's been maintained by multiple
people over a period of years.
I include the source code of dmd itself as a (bad) example of #if hell. I've
gone to some effort to beat that disease out of the front end, but like
barnacles on a boat, they always come back and threaten to sink the ship. The
back end is far worse.
There are other ways of doing versioning that do not have this result, and I
recommend giving them a chance long before reaching for this particular one.
