[Gambas-user] About arrays

[Benoît Minisini]

Hi,

This is a clarification about Gambas arrays for Demosthene and all who 
answered him.

There are two kinds of arrays in Gambas:
- "Normal" arrays.
- "Embedded" arrays.

Fabien used the word "static" arrays for "embedded" arrays because this was 
the word I used first. Then I changed to "embedded" to avoid any confusion 
with the "STATIC" keywords, which is not related at all.

"Normal" arrays are true Gambas objects. They have their own memory 
allocation, and they are destroyed when they are not referenced anymore.

To declare a "normal" array, you can do:

	(1) Dim NormalArray As Type[]
	(2) Dim NormalArray As Type[] = [ ... ]
	(3) Dim NormalArray As Type[] = New Type[A, B]
	(4) Dim NormalArray As Type[A, B]

(1) declares an object variable that can receive a reference to a array whose 
type is "Type[]". "Type" can be a native datatype or a class name. Note that 
in Gambas 2, "Type" can only be a native datatype.

(2) declares an object variable, and initializes it with a new array created 
by the [ ... ] operator.

(3) declares an object variable, and initializes it with a new array hainvg 
the specified dimension.

(4) is a shortcut to the (3) syntax.

"Embedded" arrays are arrays that are allocated *inside* another object. They 
don't have a memory allocation on their own, and they are automatically freed 
with the object including them.

"Embedded" arrays are always member of a class or a structure only.

To declare an "embedded" array, you do the following:

	[Static] {Private|Public} EmbeddedArray[A, B] As Type

There, "Type" is the datatype of one element of the array. There is no "[]" 
after the type, unless you want to store array references inside the array of 
course.

"Embedded" arrays can be static or not, public or private.

"Embedded" arrays are a little bit slower than normal arrays.

They were created to mimic C arrays (like Gambas structures, that were created 
to mimic C structures), so that working with extern C functions using arrays 
and structures is possible. 

So you should not use them, unless you are working with extern functions.

I hope Gambas arrays are clearer now!

Regards,

-- 
Benoît Minisini