c++ - Output a C array through ostream -

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i'm trying output c array using iostream.

for array of ints, wrote code this

template <size_t n> ostream& operator<< (ostream& os, const int (&x)[n]) {     for(int i=0; i<n; i++)         os<<x[i]<<",";     return os; } int main() {     int arr[]={1,2,3};     cout<<arr<<endl;     return 0; }

and works pretty fine.

then, i'd generalize more types (like chars, floats etc), update original version follows

template <class t, size_t n> ostream& operator<< (ostream& os, const t (&x)[n]) {     for(int i=0; i<n; i++)         os<<x[i]<<",";     return os; }

the main function didn't change, however, time, when compile it, error occured.

in function `std::ostream& operator<<(std::ostream&, const t (&)[n]) [with t = int, long unsigned int n = 3ul]': a.cpp:15:   instantiated here a.cpp:9: error: ambiguous overload `operator<<' in `(+os)->std::basic_ostream<_chart, _traits>::operator<< [with _chart = char, _traits = std::char_traits<char>]((*((+(((long unsigned int)i) * 4ul)) + ((const int*)x)))) << ","' /usr/lib/gcc/x86_64-redhat-linux/3.4.5/../../../../include/c++/3.4.5/bits/ostream.tcc:121: note: candidates are: std::basic_ostream<_chart, _traits>& std::basic_ostream<_chart, _traits>::operator<<(long int) [with _chart = char, _traits = std::char_traits<char>] <near match> /usr/lib/gcc/x86_64-redhat-linux/3.4.5/../../../../include/c++/3.4.5/bits/ostream.tcc:155: note:                 std::basic_ostream<_chart, _traits>& std::basic_ostream<_chart, _traits>::operator<<(long unsigned int) [with _chart = char, _traits = std::char_traits<char>] <near match> /usr/lib/gcc/x86_64-redhat-linux/3.4.5/../../../../include/c++/3.4.5/bits/ostream.tcc:98: note:                 std::basic_ostream<_chart, _traits>& std::basic_ostream<_chart, _traits>::operator<<(bool) [with _chart = char, _traits = std::char_traits<char>]

how can fix this? thank suggestions.

there exists overload operator << (const char*) ambiguous template.

you may restrict template sfinae exclude char:

template <class t, size_t n,      typename = typename std::enable_if<!std::is_same<char, t>::value>::type> ostream& operator<< (ostream& os, const t (&x)[n])

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