[LLVMdev] Using C++'11 language features in LLVM itself

[Richard Smith]

On Tue, Jan 8, 2013 at 6:23 PM, Chris Lattner <clattner at apple.com> wrote:
> On Jan 8, 2013, at 4:26 PM, Jeffrey Yasskin <jyasskin at googlers.com> wrote:
>>> Another thing to bring up is that we have a lot of classes which have
>>> method pairs `foo_begin()` and `foo_end()` (e.g.
>>> `Function::arg_{begin,end}()`). These don't play nice with range-for
>>> loops (we are already seeing this come up in LLD). We probably should
>>> adopt some lightweight "range" class and a naming convention
>>> (`foo_all()`?) that will interact well with range-for. jyasskin, you
>>> have some standards proposals for such a class, maybe you could try
>>> bringing that into tree?
>>
>> The C++ proposal changes rapidly. While it would be great to get usage
>> experience from LLVM in order to inform the C++ proposal, I don't have
>> "what will eventually be in C++" to propose for LLVM. Well, I'd expect
>> some "range<IteratorType>" template with .begin() and .end() methods,
>> but I don't even know what name that template will have.
>>
>> I'm not sure this part of the discussion is on-topic for Chris's
>> thread, since it's not related to a potential problem with enabling
>> C++ language features. (Not having a range type doesn't make
>> range-based for loops fail to compile on some platform, it just makes
>> them slightly less useful.)
>
> One other specific problem with this is that (I'm told) MSVC 2010 doesn't support range-based for loops.  I don't think it is reasonable to require windows users to be on MSVC 2012.  :-(

I suspect you're right about that, but I'd appreciate if some MSVC
users would speak up here. We shouldn't hold back on using range-based
for loops if all our MSVC users are happy to move to MSVC 2012
(assuming no problems with other platforms).