Subject: Re: [boost] [range] - Proposal to change the indexed range adaptor
From: Robert Jones (robertgbjones_at_[hidden])
Date: 2010-10-31 17:02:19
On Sun, Oct 31, 2010 at 8:43 PM, Neil Groves <neil_at_[hidden]>wrote:
> On Sat, Oct 30, 2010 at 6:28 PM, Robert Jones <robertgbjones_at_[hidden]
> > On Sat, Oct 30, 2010 at 12:38 PM, Neil Groves <neil_at_[hidden]
> > >wrote:
> > >
> > > I propose that a breaking change is made to the index range adaptor so
> > that
> > > it returns a pair<original_reference_type, index_type>.
> > >
> > >
> > Hi Neil
> > Could you provide a use-case example, before and after.
> Certainly. I should have thought to do this in the original email. Thank
> for taking the time to help me acquire information.
> BOOST_FOREACH( auto item, rng | index )
> // access to the index is not possible - doh :-(
> // The return type of the dereferenced element from an index range
> adaptor loses the index
> const element_type& elem = item;
...so in the 'BEFORE' case, how can this be written now, with your
library as it stands (presumably not with BOOST_FOREACH)?
ps. I must, rather sheepishly, admit to not having been able to use your
library in real code - sorry! Having actively encouraged you write it, I
personally am constrained to 1.39 and before - doesn't that just suck!
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