string class

[cppnoob25]

What am I doing wrong here?

#include <iostream>

using namespace std;

class String {
        int size;
        char * buffer;
        int strlen(const char *s)
        {
            for(int i = 0; s[i] != '/0'; i++)
                return i;
        }
public:
        String();
        String(const String & s);
        String(const char *p);
        ~String();
        int length();

	// other methods

        friend bool operator==(const String &, const String &);
        friend bool operator<=(const String &, const String &);
        friend bool operator<(const String &, const String &);
        friend ostream & operator<<(ostream &, const String &);
};

String::String()
{
    buffer = 0;
    size = 0;
}

String::String(const String & s)
{
    size = s.size;
    buffer = new char[size];
    for(int i =0; i < size; i++)
    {
        buffer[i] = s.buffer[i];
    }
}

String::String(const char *p)
{
    size = strlen(p);
    buffer = new char[size];
    for(int i = 0; i < size; i++)
    {
        buffer[i] = p[i];
    }
}

int String::length()
{
    return size;
}


String::~String()
{

}

ostream & operator<<(ostream &os, const String &s)
{
    os << String(s);
    return os;
}



#include <cassert>

using namespace std;

int main()
{
   String s1; // s1 == ""
   assert(s1.length() == 0);

   String s2("hi");  // s2 == "hi"
   cout << s2;
   //assert(s2.length() == 2);
}

I believe there's something wrong with my
ostream & operator<<(ostream &os, const String &s)

But there might be more errors in this code. It compiles but then crashes when ran.

[D80DSL3A]

You must allow space for a terminating null '\0' in your string object.

String::String(const char *p)
{
    size = strlen(p);
    buffer = new char[size+1];// one extra for the '\0'
    for(int i = 0; i < size; i++)
    {
        buffer[i] = p[i];
    }
    buffer[size] = '\0';// assign as last element
}

Yes, there is a problem in operator<<
Instead of os << String(s);// a constructor returns nothing. Not even void!
Do this: os << s.buffer;
The destructor needs work too.

[ats15]

A few minor bugs:

        int strlen(const char *s)
        {
            int i=0;
            for( i = 0; s[i] != '\0'; i++){}
            return i;
        }

Note the \0 instead of /0 and also you want to finish the for loop before you return i
In the operator <<, use os << s.buffer;

[cppnoob25]

Thanks it all works perfectly now. Now to continue this until I get more of the string class working.