Contents  Introduction  An Overview  Starting from  Familiar Ground  Source code  Printable version  Discuss this article The Series  An Introduction  Data Manipulation  Dynamic Loading  The Stack and  Program Flow

Introduction

This series is intended to give the reader the information necessary to create a scripting system of his/her own from the ground up. The reasons one would choose to create such a system from scratch are many, most of which are analogous to reasons one would create anything else from scratch, such as a 3D engine. Most importantly, in my opinion, is that it's a valuable learning experience. After all, who doesn't want to learn? Certainly nobody who is taking the time to read this article!

Many of the articles devoted to scripting that I've seen in the past do not do enough to cater to the practical-minded programmers. These are the programmers who wish to learn about how the entire process of bringing a script from a high-level language down to some procedural format relates to their own programming efforts. They want to design a system that suits their needs, without being clouded by complexity. As such, this series will be geared towards enabling a programmer to fashion his/her own system, and not be dependent on handout code. Hopefully this series will be helpful to those who have found these other articles lacking as described. (No offense intended to anyone who may have written an article on scripting. Please don't take this personally.)

In addition, this series will include example code snippets written in C++. It's recommended that you be at least familiar with the basics of C++ classes.

Basic Format of this Series

The format of this series will be somewhat reversed with respect to the seemingly "normal" approach. I will not begin with the high-level language and end with the low-level implementation. Rather, I will be using a bottom-up approach, as it is more natural to develop a scripting system in this manner. A significant advantage of this approach is that the code immediately produces results, allowing problems to be found much more easily, and before they become serious. This is in direct contrast to tutorials which would begin with language theory, and ask that the programmer maintain faith that eventually somewhere down the line, everything will work itself out, and be free of bugs.

This first article will provide a simple overview to gain some perspective on what the purpose of a scripting system is, the problems it is usually intended to solve, and possible implementations. A simple example will be provided, and built upon in future articles.

A rough outline of future articles is as follows:

• First, more fully described low-level characteristics of the form of implementation that I will be writing about.
• They will then move on to mechanisms for "embedding" this system into an already existing game or application system.
• The topics involving language theory, parsing, and compiling will possibly conclude the series.

This outline is considered rough to leave options open for new things, depending mostly on feedback to this first article. So please, let me know what you think.

Next : An Overview