Re: [boost] VC8 no ADL in some cases

From: Andy Little (andy_at_[hidden])
Date: 2006-01-23 23:14:50

It might have something to do with operations on temporaries in parentheses?

Whatever heres more context to my other example example .  Note if you want to 
try this out in  pqs
_3_0_4 you need to add boost::pqs::  in front of  t1_quantity at line 143
In <boost/pqs/t1_quantity/operations/add_subtract.hpp>. Thats an error in
pqs_3_0_4 but only affects VC8
Then in the same file disable the conditonal defines for vc8 around  namespace
open and  close parentheses  for operator +  and operator  - .

Maybe this will work on simpler udts in the same sort of situation. Will try 
this
next.

#include <boost/pqs/t1_quantity/types/out/velocity.hpp>
#include <boost/pqs/t1_quantity/types/out/acceleration.hpp>
#include <boost/pqs/t1_quantity/types/out/time.hpp>

// Note all operators except addition/subtraction
// are defined in global namespace for this test

// #define FUNC1 only   --> compiles OK
// #define FUNC1 and FUNC2 -->  compiles OK
// #define FUNC2 --> error no '-' operator found

#define FUNC1
#define FUNC2

#ifdef FUNC1
boost::pqs::acceleration::m_div_s2
Func1(
 const boost::pqs::velocity::mm_div_s& a,
 const boost::pqs::velocity::m_div_s& b,
 const boost::pqs::time::s & t
)
{
 // succeeds not affected by parentheses;
 boost::pqs::velocity::m_div_s v = (a - b);
 // succeeds
 //boost::pqs::velocity::m_div_s v =  a - b;

    boost::pqs::acceleration::m_div_s2  result =  v / t;
 return result;
}
#endif

#ifdef FUNC2
boost::pqs::acceleration::m_div_s2
Func(
 const boost::pqs::velocity::mm_div_s & a,
 const boost::pqs::velocity::m_div_s& b,
 const boost::pqs::time::s & t
)
{
 // fails
    boost::pqs::acceleration::m_div_s2  result =  (a-b) / t;
 // fails
 // boost::pqs::acceleration::m_div_s2  result =  1 / (t / (a-b));
 // succeeds
 //boost::pqs::acceleration::m_div_s2  result =  (boost::pqs::operator-(a, b)) /
t;
 // succeeds
    //boost::pqs::acceleration::m_div_s2  result =  a / t - b/ t;

 return result;
}
#endif