arrays
The language implemented by ScriptBasic for Java can handle arrays. The arrays are allocated on the fly and are indexed from zero up to their limits. If you try to index an array above the actual limit the array is automatically extended.
The following program creates an array and sorts it with the simplest possible bubble sort:
a[0] = 3
a[1] = 2
a[2] = 7
a[3] = -1
a[4] = 58
a[5] = 0
a[6] = 99
for i=0 to length(a)-1
for j=0 to length(a)-1
if a[i] < a[j] then
x = a[i]
a[i] = a[j]
a[j] = x
endif
next j
next i
for i=0 to length(a)-1
print a[i],"\n"
next i
For programming safety reasons you can not use a variable to store a non array value that already stores an array. For example the following code will result error:
' This code will not work
a[13] = 2
a = 55
This will prevent programming errors and avoid some misbehaving scripts. On the other hand you can use a variable to hold an array that was storing some value before:
' This code works fine
a = 55
a[13] = 2
The only value you can assign to a variable that is already an array is the undefined value. To do that is very simple, you can write
' This code will work
a[13] = 2
a = undef()
a = 55
undef() is a predefined function that returns the undefined value.
The length of an array can be retrieved using the function length(). Note that arrays are
indexed from zero up. This means that the index values that hold meaningful values are from 0 to
length(array)-1. When you use an index that is larger than length(array)-1 the array will
automatically be extended with undefined members. Therefore it is very
easy to allocate really great amount of memory in ScriptBasic for Java using some large index values when
setting or reading array elements.
To prevent the creation of too large arrays ScriptBasic can be configured with the configuration
key arrayMaxIndex to limit the maximum size an array can be indexed with. If an index is larger than
the configured limit the BASIC interpreter withh throw an exception.
