1. Welcome Back
2. The Buffer Class
3. An Abrupt End

Welcome Back

Last time, we finished the basic skeleton, and now it is time to implement some functions! Let's do some easy ones first.

The Buffer Class

Create a file Buffer.cpp. This all should be fairly straightforward and easy to understand. We'll set up first.

#include "Buffer.h"

Buffer::Buffer() {}

Let's have fun with recursion now, and do the remTabs(string) function!

string Buffer::remTabs(string line)
{
    int tab = line.find("\t");
    if(tab == line.npos)
        return line;
    else
        return remTabs(line.replace(tab, 1, "    "));
}

Keep in mind that there are 4 spaces in the string. This function recursively finds a tab in a line. When a tab is found, it goes again until no more tabs could be found, then returns the line.

Now for some helper functions for line operations. These are not really necessary but are asthetically pleasing should you use them in your Editor.cpp file (which you will). It makes your code there more readable (I think).

void Buffer::insertLine(string line, int n)
{
    line = remTabs(line);                   // Conversion (happens every time)
    lines.insert(lines.begin()+n, line);
}

void Buffer::appendLine(string line)
{
    line = remTabs(line);
    lines.push_back(line);
}

void Buffer::removeLine(int n)
{
    lines.erase(lines.begin()+n);
}

An Abrupt End

And that's it till next time! You are ready for Part 3!