Re: [Boost-users] [review][assign] Formal review of Assign v2 ongoing

Subject: Re: [Boost-users] [review][assign] Formal review of Assign v2 ongoing
From: John Bytheway (jbytheway+boost_at_[hidden])
Date: 2011-07-02 05:06:39

On 24/06/11 03:17, Steven Watanabe wrote:
> AMDG
> 
> On 06/23/2011 03:45 PM, John Bytheway wrote:
>> On 21/06/11 23:05, Simonson, Lucanus J wrote:
>>>           v_ v1 = {
>>>               { "a", 1 },
>>>               { "b", 2 },
>>>               { "c", 3 },
>>>               { "d", 4 },
>>>               { "e", 5 }
>>>           };
>>>
>>> Arguably the extra {} around each vector element in the new
>>> initializer syntax is more readable than the proposed assign
>>> v2 syntax.  Tuple and deque support initializer list as do
>>> all classes with constructors and structs.
>>
>> For what it's worth, your particular example doesn't work in gcc 4.5
>> because the relevant constructor of std::tuple's is explicit (I wasn't
>> aware of this effect of marking a constructor explicit, and I'm quite
>> surprised...).  The analogous example with std::pair works fine.
>>
> 
> Yep.  You have to use
> 
> v_ v1{
>     { "a", 1 },
>     { "b", 2 },
>     { "c", 3 },
>     { "d", 4 },
>     { "e", 5 },
> };

That doesn't work in gcc 4.5 either; I get the same error about use of
an explicit constructor.

John