[Development] Proposal: Deprecating platforms in Qt 5.6 that don't support lambda

Thiago Macieira thiago.macieira at intel.com
Fri Feb 20 20:47:39 CET 2015

On Friday 20 February 2015 13:37:16 Matthew Woehlke wrote:
> On 2015-02-19 20:26, Thiago Macieira wrote:
> > Do NOT do this. This will crash:
> > 	for (auto const &item : std::cref(somefunction()) { ... }
> Does it crash without the std::cref? 

No, due to lifetime extension of the temporary.

> If not... seems like a good argument to support a free 'const'...
> > And another reason is that std::cref is a C++11 Standard Library addition
> > and we cannot depend on that yet.
> ...but so is range-based for (and auto).

That's different, those are core language features and we have Q_COMPILER_xxx 
for them.

Standard Library features are more difficult to detect and even the library 
providers are lagging behind:


Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel Open Source Technology Center

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