Thread: Bad feeling about piece of code

That return statement is no different to:

Code:

	return string((const char *)buffer);

So, as that shows, it is actually just fine.

Originally Posted by iMalc

That return statement is no different to:

Code:

	return string((const char *)buffer);

So, as that shows, it is actually just fine.

Of course, it would make it more obvious to write it this way than the originally posted code. And making things obvious always helps!

--
Mats

Even then, what's the point in the cast to const char*?

Originally Posted by anon

Even then, what's the point in the cast to const char*?

It is probably not necessary in an explicit conversion. The compiler is unlikely to automatically convert a char [] into a string, but by casting, it finds the string(const char *) constructor, and is "happy" to compile the code. using explicit string(buffer) should work - I haven't tried it, but it's likely to work OK.

--
Mats

In case you're interested, here's how you could do it using stringstreams:

Code:

#include <string>
#include <sstream>

std::string ltos(long number) {
    std::ostringstream stream;
    stream << number;
    return stream.str();
}

My favourite method, though, is to use something like this.

Code:

#ifndef CALLIS_MISC_STREAM_AS_STRING_H
#define CALLIS_MISC_STREAM_AS_STRING_H

#include <sstream>
#include <string>

namespace Callis {
namespace Misc {

/** A simple class which in effect that adds an insertion operator, <<, to the
    std::string class, as users of streams such as cout or stringstream expect.

    This class can be used as a temporary object in places where an ordinary
    string would be expected; for example:
        void print(std::string str);
        print(StreamAsString() << "Answer = " << 42);

    This implementation is quite efficient, only converting its internal
    stringstream to a string when operator std::string() is called.
*/
class StreamAsString {
private:
    /** The internal stringstream used to implement the insertion operator <<.
    */
    std::ostringstream stream;
protected:
    std::ostringstream &get_stream() { return stream; }
    const std::ostringstream &get_stream() const { return stream; }
public:
    /** Adds an object to the end of the internal stringstream.
    */
    template <typename T>
    StreamAsString &operator << (const T &data);

    /** Converts the internal stringstream to an std::string automatically.
    */
    operator std::string() const;
};

template <typename T>
StreamAsString &StreamAsString::operator << (const T &data) {
    get_stream() << data;

    return *this;
}

inline StreamAsString::operator std::string() const {
    return get_stream().str();
}

}  // namespace Misc
}  // namespace Callis

#endif

Then as the comment indicates you can use code like

Code:

long long_answer = 42;
std::string answer = StreamAsString() << long_answer;

and the StreamAsString object will automatically be converted to a std::string.