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From: Atry (pop.atry_at_[hidden])
Date: 2007-06-02 14:38:08
Atry wrote:
> Giovanni Piero Deretta wrote:
>> On 6/2/07, Atry <pop.atry_at_[hidden]> wrote:
>>
>>> #include <boost/typeof/typeof.hpp>
>>> #include <boost/static_assert.hpp>
>>> int a = 0;
>>> int& b = a;
>>> BOOST_STATIC_ASSERT((boost::is_same<BOOST_TYPEOF(b), int&>::value));
>>>
>>>
>>
>> IIRC (do not have the docs at hand right now), BOOST_TYPEOF drops
>> toplevel references. So does gcc builtin typeof and, I think, the
>> proposed 'auto' type deduction (while decltype should preserve them).
>>
>> HTH,
>>
>> gpd
>> _______________________________________________
>> Unsubscribe & other changes:
>> http://lists.boost.org/mailman/listinfo.cgi/boost
>>
>>
> Thanks. But is there any way to determine if an expression is reference?
>
>
In other word, how to know whether the expression is l-value;
#include <iostream>
void x(int&)
{
std::cout << "l-value" << std::endl;
}
void x(int)
{
std::cout << "r-value" << std::endl;
}
int main()
{
x(1); // r-value;
int i = 1;
int& j = i;
x(i); // expect l-value, but error.
x(j); // expect l-value, but error.
}
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