The importance of variables in any programming language can’t be emphasised enough. Even if you are a novice, the chances are good that you will have been using variables for quite a while now.

They are the cornerstone of any language and without them we would not be able to accomplish much of anything. However, most of you up until this point have probably only been working with standard variables, variables which can hold single values such as an integer, a single character, or a string of text.

In this tutorial we are going to take a look at a more special type of variable called an array. Arrays can seem quite daunting at first glance but once you get used to working with them you will wonder how you ever managed to program without them.

The reason arrays are special is because they can hold more than one value. Think about this: say you create a variable which contains a line of text like the code below:

Checking to see if a directory exists and then creating it if it is not present requires a few lines of code.  Isn't Python great.   Begin by importing the os module and use the exists and makedirs functions.

import os

if os.path.exists(somedirectory):
   os.makedirs(somedirectory)

Recently, I asked my friend, Ray, to list those he believes are the top 10 most forward thinkers in the IT industry.  Below is the list he generated. 

Like most smart people, Ray gets his information from institutions such as the New York Times, the Wall Street Journal, the Huffington Post, Ted Talks ...  Ray is not an IT expert; he is, however, a marketer: the type that has an opinion on everything and is all too willing to share it.  Unfortunately, many of his opinions are based upon the writings/editorials of those attempting to appeal to the reading level of an 8th grader.  I suppose it could be worse.  He could be referencing Yahoo News, where important stories get priority placement such as when the voluptuous Kate Upton holds a computer close to her breasts.

Before you read further, note that missing from this list and not credited are innovators: Bill Joy, Dennis Ritchie, Linus Torvalds, Alan Turing, Edward Howard Armstrong, Peter Andreas Grunberg and Albert Fent, Gottfried Wilhelm Leibniz/Hermann Grassmann ... You know the type:  the type of individual who burns the midnight oil and rarely, if ever, guffaws over their discoveries or achievements.

Structure Rule Language

To aid in the ease of rule authoring, Blaze Software, now Fair Isaac, created the proprietary Structure Rule Language (SRL), an object-oriented programming language designed to enable those with little or no background in software development to pen rules. Although the capabilities of this language are far too extensive to detail in this article, we can examine the basic rule syntax.

Rules in the SRL take the following form:

rule RuleName [at | priority M] is