Re: Templates, Boost tuples & Three compilers
On Jul 16, 5:12 pm, Alex Vinokur <ale...@users.sourceforge.net> wrote:
Hi,
Here is some program.
It was compiled with three compilers.
BOOST Version: 1_34
--- HP-UX, aCC ---
aCC: HP C/aC++ B3910B A.06.15 [May 16 2007]
aCC +DD64 -AA -I/adjhome/ip/ccadj/ccadj/BOOST/boost_1_34_0 prog1.cpp
// No errors
--- AIX, xlC ---
IBM XL C/C++ Enterprise Edition V8.0 for AIX
xlC_r -q64 -qwarn64 -I/usr/local64/boost_1_34_0 prog1.cpp
// No errors
--- Linux, icpc ---
Intel(R) C++ Intel(R) 64 Compiler Professional for applications
running on Intel(R) 64, Version 11.0
icpc -I/adjhome/adj/ccadj/ccadj/BOOST/boost_1_34_0 prog1.cpp
prog1.cpp(47): error: expected an expression
v.push_back (t.get<I>());
^
prog1.cpp(62): error: expected an expression
v.push_back (t.get<0>());
^
detected during instantiation of
"std::vector<boost::tuples::element<0, T>::type,
std::allocator<boost::tuples::element<0, T>::type>> Foo<T,
I>::tuple2vector(const T &) [with T=boost::tuples::tuple<int, int,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type,
boost::tuples::null_type, boost::tuples::null_type>, I=1UL]" at line
80
compilation aborted for prog1.cpp (code 2)
--------------
Something is wrong?
Yes, something is wrong in the code.
Thanks.
Alex Vinokur
========= prog1.cpp =========
<snip>
// --------------------------------------
template <class T, std::size_t I>
class Foo
{
BOOST_STATIC_ASSERT (I < boost::tuples::length<T>::value);
public:
typedef typename boost::tuples::element<0,T>::type LocalType;
static std::vector<LocalType> tuple2vector (const T& t)
{
std::vector<LocalType> v = Foo<T, I-1>::tuple2vector(t);
v.push_back (t.get<I>());
^^^^^^^^^^
As t is a dependent name, the compiler may (should) need some
assistence here to realise you are using a template member of t:
v.push_back (t.template get<I>());
return v;
}
};
template <class T>
class Foo<T, 0>
{
public:
typedef typename boost::tuples::element<0,T>::type LocalType;
static std::vector<LocalType> tuple2vector (const T& t)
{
std::vector<LocalType> v;
v.push_back (t.get<0>());
Same here.
return v;
}
};
<snip>
=========================
=====
Bart v Ingen Schenau