Undefined reference to function

[bmw]

I am getting an Undefined reference to function and I can't figure out why.

The error is: main.cpp|288|undefined reference to `HTML::getHeadAndBody(std::string, std::string*, std::string*)

main.h:

#include <iostream>
#include <windows.h>
#include <string.h>
#include <sstream>
#include <fstream>

class HTML
{
    public:
    static int getHeadAndBody(std::string document, std::string* head, std::string* body);
    static void lowercase(char* in, char* out);
};

main.cpp:

#include "main.h"

using namespace std;

int getHeadAndBody(std::string document, std::string* head, std::string* body)
{
    //Make a buffer(for storing the tag names e.g. html or title
    char buf[500];
    //Make a integer so we know the current character
    int currchar = -1;
    //Loop until we find the first opening bracket (<)
    for(int i=0; i<document.length(); i++)
    {
        if(document[i] == '<')
        {
            //We have found a <. Set the currchar to the current character, and break from the loop.
            currchar = i;
            break;
        }

    }
    //If the loop did not find a <, the currchar will remain as -1.
    //If currchar is -1, we must exit the function as the html file is not valid.
    if(currchar==-1)
    {
        return 1;
    }
    //Create a count integer for use with the buffer
    int count = 0;
    //Loop until we find the closing bracket (>) or the end of the document.
    while(1)
    {
        //Increment currchar by 1
        currchar++;
        //Check if we have found the closing bracket.
        if(document[currchar] == '>')
            break;
        //Check if we have reached the end of the document. If we have we must exit the function
        //as the html file is not valid because there is no closing bracket.
        if(currchar >= document.length())
            return 1;
        //Store the character in the buffer.
        buf[count] = document[currchar];
        //Increment the count integer by 1 so we use the next buffer char next time.
        count++;
    }
    //Append a null character to the buffer to mark the end of the string.
    buf[count] = '\0';
    //Convert the strings to lower case
    //Create a buflc (buffer lower case) variable to store the lower cased buffer.
    char buflc[500];
    HTML::lowercase(buf, buflc);
    //Check if the tag was an html tag.
    if(stricmp(buflc, "html"))
    {
        //If it isnt we must exit the function as the html file is
        //not valid if the first tag is not a html tag.
        return 1;
    }
    //If the code reaches here, the tag must be html. Increment currchar.
    currchar++;
    //Set count back to 0 so we use the buffer properly.
    count = 0;
    while(1)
    {
        //Check if we have reached the end of the document.
        if(currchar==document.length())
            return 1;
        //Check if we have found the opening bracket.
        if(document[currchar]=='<')
            break;
        //Increment currchar
        currchar++;
    }
    //Set count to 0.
    count = 0;
    while(1)
    {
        //Increment currchar
        currchar++;
        //Check if we have reached the end of the document.
        if(currchar >= document.length())
            return 1;
        //Check if we have found the closing bracket.
        if(document[currchar]=='>')
            break;
        //Put the character in the buffer
        buf[count] = document[currchar];
        //Increment count.
        count++;
    }
    //Append a null character to mark the end of the string.
    buf[count] = '\0';
    //Lowercase
    HTML::lowercase(buf, buflc);
    //Check if the tag is a head tag.
    if(stricmp(buflc, "head"))
    {
        //If not exit the function.
        return 1;
    }
    //Increment currchar.
    currchar++;
    //Loop to get all the characters of the head and store them in the head string.
    while(1)
    {
        count = 0;
        if(currchar >= document.length())
            return 1;
        //Check if we have found a bracket, because it could be the end of the head.
        if(document[currchar]=='<')
        {
            while(1)
            {
                currchar++;
                if(currchar >= document.length())
                    return 1;

                if(document[currchar]=='>')
                {
                    break;
                }

                buf[count] = document[currchar];

                count++;
            }
            buf[count] = '\0';
            //Lowercase
            HTML::lowercase(buf, buflc);
            if(!(stricmp(buflc, "/head")))
            {
                //We have reached the end of the head
                break;
            }
            else
            {
                buf[count] = '\0';
                *head += '<';
                *head += buf;
            }
        }
        *head += document[currchar];
        currchar++;
    }
    //The head is now stored in the string *head

    //Check for body tag
    currchar++;
    count = 0;
    while(1)
    {
        if(currchar >= document.length())
            return 1;
        if(document[currchar]=='<')
            break;
        currchar++;
    }
    count = 0;
    while(1)
    {
        currchar++;
        if(currchar >= document.length())
            return 1;
        if(document[currchar]=='>')
            break;
        buf[count] = document[currchar];
        count++;
    }
    buf[count] = '\0';
    HTML::lowercase(buf, buflc);
    if(stricmp(buflc, "body"))
    {
        return 1;
    }
    //If the code gets to here, the body exists

    currchar++;
    while(1)
    {
        count = 0;
        if(currchar >= document.length())
            return 1;

        if(document[currchar]=='<')
        {
            while(1)
            {
                currchar++;
                if(currchar >= document.length())
                    return 1;

                if(document[currchar]=='>')
                {
                    break;
                }

                buf[count] = document[currchar];

                count++;
            }
            buf[count] = '\0';
            HTML::lowercase(buf, buflc);
            if(!(stricmp(buflc, "/body")))
            {
                //we have reached the end of the body
                break;
            }
            else
            {
                buf[count] = '\0';
                *body += '<';
                *body += buf;
            }
        }
        *body += document[currchar];
        currchar++;
    }
    //The body is now stored in the string *body

    //Check for closing html tag
    currchar++;
    count = 0;
    while(1)
    {
        if(currchar >= document.length())
            return 1;
        if(document[currchar]=='<')
        {
            while(1)
            {
                currchar++;
                if(currchar >= document.length())
                    return 1;

                if(document[currchar]=='>')
                {
                    break;
                }

                buf[count] = document[currchar];

                count++;
            }
            buf[count] = '\0';
            HTML::lowercase(buf, buflc);
            if(!(stricmp(buflc, "/html")))
            {
                //we have reached the end of the html
                break;
            }

        }
        currchar++;
    }
    //We have reached the end of the file and it is valid.
    //We have the head and body stored in the strings head and body.
    return 0;
}

void HTML::lowercase(char* in, char* out)
{
    int i = 0;
    while(1)
    {
        if(in[i]=='\0')
        {
            break;
        }
        out[i] = tolower(in[i]);
        i++;
    }
    out[i] = '\0';
}

int main()
{
    string head, body;
    ifstream htmlfile;
    htmlfile.open("C:\\file.html");
    if(!htmlfile.good())
    {
        cout << "Can't read HTML file";
        return 1;
    }
    string document((std::istreambuf_iterator<char>(htmlfile)), std::istreambuf_iterator<char>());
    //TODO:Fix This
    if(HTML::getHeadAndBody(document, &head, &body))
    {
        cout << "HTML file is valid.\n\nThe head is:\n" << head << "\n\nThe body is:\n" << body;
    }
    return 0;
}

[Pravesh Koirala]

in main.cpp line 4
write int HTML::getHeadAndBody(..)

[Zhuge]

Really...? You added the scope information to function definition and you get that error?

[bmw]

oh i see!!! i had to put HTML:: onto the definition!!! thanks for spotting that...

[bmw]

Zhuge i didn't do it properly the first time i put another whole line... like this

int HTML::getHeadAndBody(blahblahblah);

int getHeadAndBody(blahblahblah)
{
stuff;
}

but i was meant to do this:

int HTML::getHeadAndBody(blahblahblah)
{
stuff;
}

^^^works^^^

[Zhuge]

I see. Glad you were able to figure out your error.

[bmw]

Thanks everyone it is solved :D