Time for Phobos CTFE-ability unittests...right? RIGHT?

[Jonathan M Davis]

On 2011-07-20 15:37, Don wrote:
> Nick Sabalausky wrote:
> > Yet again, a new DMD release has broken my code, and other people's code,
> > too, just because of Phobos functions loosing their CTFE-ability.
> > (strip(), toLower(), etc... And yes, I did bring up the strip()
> > regression on the beta list, to no effect.)
> 
> The situation is, that prior to 2.054, use of Phobos in CTFE functions
> has not been supported. No official statements have ever been made that
> it was supported (and I've tried hard to publicize the fact that it was
> not supported). There were some fundamental wrong-code bugs and severe
> limitations in CTFE. And so although some Phobos functions seemed to
> work in CTFE, most of them were not correct.
> So, any Phobos function which used to work in CTFE in some old release
> but doesn't any more is not a regression. It was just dumb luck, relying
> on undefined behaviour, if any happened to work in a particular release.
> 
> This has changed with 2.054. Although there are still some restrictions
> (no classes, many builtin functions aren't implemented), the fundamental
> wrong code bugs are fixed. So any Phobos function which works in CTFE in
> 2.054, but fails in a future release, can be considered a regression.
> We are now in a _completely_ different regime.

If that's the case, then we should look at adding CTFEability tests to at 
least some portion of Phobos.

- Jonathan M Davis