[Development] RFC: more liberal 'auto' rules?

Thiago Macieira thiago.macieira at intel.com
Mon Dec 7 18:04:00 CET 2015

On Monday 07 December 2015 17:53:41 Olivier Goffart wrote:
> On Monday 7. December 2015 08:28:53 Thiago Macieira wrote:
> > What const is missing? Are you saying it should have been
> > 
> > 	for (const std::pair<const std::string, std::string> &e: stdMap)
> Yes.
> The value_type of a std::map<Key,T>  is std::pair<const Key, T>.
> It allows to do this:
>    // add "foobar" to all the entries
>    for (auto &e: stdMap)
>          e.second += "foobar";
> But it does not allow to change the key because that cannot be changed via
> an iterator.

Ah, right, this is a *mutating* iterator. Sorry, I missed that fact.

I was thinking of the usual read-only iteration that we get from foreach. 
Mutating with a range for is something I've never done.

> > If so, I consider that an API defect in std::map
> Quite the contrary.

I stand corrected.

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

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