Pass pointer as generic type c++ template -


i'm trying pass pointer (char*) generic function wrote. error " overloaded foo ambiguous in context ". why happen?

template <class t> t foo(t a, t b) {     return a+b; } int main() {     char *c="hello",*d="world";     foo<char*>(c,d);     return 0; }

it have no reason add 2 pointers, result in non-sensical pointer. imagine e.g. first text @ address 0x7fffff00, , second 1 in 0x80000100. after addition on 32-bit machine going get… 0. zero. null pointer!

perhaps wanted use string's instead, like:

#include <string>  template <class t> t foo(t a, t b) {     return a+b; }  int main() {     std::string c="hello", d="world";     foo(c,d);     return 0; }

also note: in many cases (like one) compiler can infer template type you, no reason write explicitly foo<std::string>(c,d).


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