Help me find the error

[fewdiefie]

Hello guys, please help me find the error in the following code:

template<class T> int to_int(const T& t)
{
	ostringstream os;
	int num = 0;

	os << t;

	string str = os.str();

	for (int i = 0; i < (int)str.length(); i++)
	{
		num += to_dig(str[i]) * pow(10, (int)str.length() - 1 - i);
	}

	return num;
}

Don't worry about to_dig(char), I wrote it to convert a character to a digit to facilitate the process.

The code is acctualy working fine but the compiler shows this warning:

note: see reference to function template instantiation 'int to_int<char[4]>(const T (&))' being compiled
1>        with
1>        [
1>            T=char [4]
1>        ]

[Peter87]

You have only posted the part that tells us where the warning is. It would be useful if you also posted the part that says what the warning is about.

[fewdiefie]

warning C4244: '+=': conversion from 'double' to 'int', possible loss of data
I didn't see it I just had to convert it to int like so

num += to_dig(str[i]) * (int)pow(10, (int)str.length() - 1 - i);

Thanks ^^

[tpb]

Normally people just say:

    num = num * 10 + to_dig(str[i]);

[Ganado]

// Example program
#include <iostream>
#include <sstream>
#include <string>

template <class T>
int to_int(const T& t)
{
	std::stringstream ss;
	ss << t;
	
	// probably wanna do some sort of error checking...
	int num = 0;
	ss >> num;
	return num;
}

struct Foo {};

std::ostream& operator<<(std::ostream& os, const Foo& foo)
{
    return os << 42;
}

int main()
{
    int a = to_int("90");
    int b = to_int(Foo());
    std::cout << a << " " << b << std::endl;
}