27.ostream.inserters.stdcxx-51.cpp

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#include <cassert>
#include <cstdio>
#include <limits>
#include <sstream>
 
 
template <class FloatT>
bool test (const char *tname)
{
    // zero and one used to verify sanity
    const FloatT zero =  FloatT ();
    const FloatT pone = +FloatT (1);
    const FloatT none = -FloatT (1);
 
    // positive and negative Infinity
    const FloatT pinf = +std::numeric_limits<FloatT>::infinity ();
    const FloatT ninf = -std::numeric_limits<FloatT>::infinity ();
 
    // positive and negative Quiet NaN
    const FloatT pqnan = +std::numeric_limits<FloatT>::quiet_NaN ();
    const FloatT nqnan = -std::numeric_limits<FloatT>::quiet_NaN ();
 
    // positive and negative Signaling NaN
    const FloatT psnan = +std::numeric_limits<FloatT>::signaling_NaN ();
    const FloatT nsnan = -std::numeric_limits<FloatT>::signaling_NaN ();
 
    std::ostringstream out;
 
    out << "     0.0:  " << zero  << '\n'
        << "  +/-1.0:  " << pone  << ' ' << none  << '\n'
        << "  +/-INF:  " << pinf  << ' ' << ninf  << '\n'
        << "  +/-QNAN: " << pqnan << ' ' << nqnan << '\n'
        << "  +/-SNAN: " << psnan << ' ' << nsnan << '\n';
 
    // expected output
    const char expect[] = {
        "     0.0:  0\n"
        "  +/-1.0:  1 -1\n"
        "  +/-INF:  inf -inf\n"
        "  +/-QNAN: qnan -qnan\n"
        "  +/-SNAN: snan -snan\n"
    };
 
    bool pass = true;
 
    if (expect != out.str ()) {
        std::fprintf (stderr, "Expected (%s):\n%s\nGot:\n%s\n",
                      tname, expect, out.str ().c_str ());
        pass = false;
    }
 
    // clear string and set the uppercase bit in flags
    out.str ("");
    out.setf (out.uppercase);
 
    out << "     0.0:  " << zero  << '\n'
        << "  +/-1.0:  " << pone  << ' ' << none  << '\n'
        << "  +/-INF:  " << pinf  << ' ' << ninf  << '\n'
        << "  +/-QNAN: " << pqnan << ' ' << nqnan << '\n'
        << "  +/-SNAN: " << psnan << ' ' << nsnan << '\n';
 
    // expected output
    const char EXPECT[] = {
        "     0.0:  0\n"
        "  +/-1.0:  1 -1\n"
        "  +/-INF:  INF -INF\n"
        "  +/-QNAN: QNAN -QNAN\n"
        "  +/-SNAN: SNAN -SNAN\n"
    };
 
    if (EXPECT != out.str ()) {
        std::fprintf (stderr, "Expected (%s):\n%s\nGot:\n%s\n",
                      tname, EXPECT, out.str ().c_str ());
        pass = false;
    }
 
    return pass;
}
 
 
int main ()
{
    bool pass;
 
    // exercise the formatting of Infinities and NaNs
    pass = test<float>("float");
    pass = test<double>("double") && pass;
 
#ifndef _RWSTD_NO_LONG_DOUBLE
 
    pass = test<long double>("long double") && pass;
 
#endif   // _RWSTD_NO_LONG_DOUBLE
 
    assert (pass);
 
    return 0;
}