Introducing References (Important!)

So far, all of our parameters have returned one result from the range or list of possible results.

$p=range(1,100)

For example, $p will always return ONE number from the full range of available numbers.

Not all parameters are this simple!

Some parameter types return two or more results. Some parameter values need to be used as a set or a list of data. What we need is a way of referencing each individual entry in these parameters.

Enter references!

If a parameter contains more than one value, you can reference an individual value using this notation:

$p[1]        The first entry

$p[2]        The second entry

$p[3]        The third entry

and so on.

References add significant power to the parameter system and we will be discussing them in more detail later on. For the moment, let's look at parameter types that rely on references for their use.