Graham, in that example, DIM MAP[0] is creating an array with no elements. This is because the LOAD function is automatically resizing it as needed for the map, but this is a special case. Generally you will want to create arrays when you want to store several values of the same type (a bunch of numbers, or a bunch of strings). Arrays are handy because they are contiguous, meaning each element follows one after the other. So you can access them using an index. This fits nicely with things like loops that use incremental numbers. Not to mention, they are good for organizing large sets of data. Consider the following:
DIM TMP[5]
TMP[0]="A"
TMP[1]="B"
TMP[2]="C"
TMP[3]="D"
TMP[4]="E"
VAR M = 0
FOR M=0 TO LEN(TMP)-1
PRINT TMP[M]
NEXT
PUSH TMP, "F"
PRINT TMP[5]
The above code creates an array with five elements, and then assigns each of them a string value. The for loop is able to access each element by the numerical index 'M'. When M is 0, it prints "A", when it's 1 it prints "B", and so on. Then at the end, the PUSH statement adds a 6th element "F", and prints it. This is a just simple example of how to use an array, but highlights some of the strengths. It's often handy to be able to look up a value based on a numerical index as opposed to a variable name. Like if you had 100 enemies in your game, would you want to do this: "VAR ENEMY1,ENEMY2,ENEMY3,..." for all 100 of them? It's much easier to do this: "DIM ENEMIES[100]"
The second is much easier to define, is organized under one label, you can perform operations on every element quickly with a FOR loop, and you can add or remove items as needed. Hope that helps.
