[APBeta] Scripting question

[RPEHLM]

Classes are really good for this sort of thing; use them a lot myself.  
Don't forget you can use the 'public' or 'private' prefix to control the 
scope (visibility) of stuff inside your class.  It's certainly possible 
to build arrays of classes.

Also useful are structures (can only be used inside a class or module); e.g.

public structure Blah
    flag as boolean
    index as integer
    name as string*20
end stucture

Note the *20 for the string declaration.  Strings in structures are 
fixed length and padded with ASCII 0, so Len() will always return 20 in 
this particular case.  Due to the way structures are implemented in 
RealBasic they cannot contain any data types whose length can vary.  For 
example 'a() as string' is out

The new Dictionary class is really really useful.  You can build a 
dictionary where the Value holds a structure, an array, or a class, or 
even an array of classes or structures (haven't tried OLEObjects yet! 
:-D).  One interesting feature of dictionaries of structures is that 
dictionary.value(key) will return the first element of the structure.  
Not sure if this is a RealSoftware bug or feature though :)

I have been trying to use enums.  So far I can declare them but have not 
been able to use them.

The SQL class offers a whole new world of data storage and retrival 
possibilities.  I have only just started looking at this but it appears 
to be really amazing.  One of the best features is the ability to create 
a database in memory; useful for short term storage.

A useful resource for APScript are the RealBasic Language Reference 
(RBLR) and User Guides (RBUG).  (<http://www.realsoftware.com/download>) 
and scroll down to the 'Individual Files' section.  Your first stop 
should be the RBScript class section in the RBLR.  You do have to employ 
some trial and error to find out what will and what won't work in a 
script.  This is where the 'Check for Errors' button is really useful!

Another useful new class is RegEx.  Haven't used it much yet but it 
should make checking user input or analysing file content a lot easier.

Hope this helps
Robin

Paul Rodman wrote:
>
> On Apr 18, 2009, at 02:35 PM, Michael Portuesi wrote:
>
>> Does the AP scripting language allow one to create objects from 
>> within a script?
>
>
>> The number of global variables in my charts script frightens me, as 
>> does the number of parameters I have to pass to each of the functions 
>> within the script.  I'd like to create an object to hold all these 
>> values, or perhaps a hash table that will store this blob of 
>> information as a set of named attributes.
>>
>> Without these sorts of language tools, it becomes difficult to build 
>> any sort of large-scale scripts inside AstroPlanner.  (I realize this 
>> is directed at the compiler vendor, not you, but I had to vent).
>
> Yes, it does (V1 and V2 for that matter)
>
> e.g.
>
> class MyClass
>   dim property1 as integer
>   dim property2 as string
>
>   sub Constructor()
>      property1=77
>      property2="Sunset Strip"
>
>   function Squodge() as string
>     return str(property1) + " " + property2
>   end function
> end class
>
> sub main()
>   dim a as MyClass
>
>   a = new MyClass
>   print a.Squodge
> end sub
>
>
> and so on.
>
> I use a lot of classes in the 10,000+ line framework which is 
> prepended to each script (See Script->Framework Reference).
>
> Note that in 2.0b34 I introduced a Dictionary class that allows you to 
> set up a "hash table" for storing and retrieving stuff.
>
> e.g.
>
> dim d as new Dictionary
>
> d.Value("Param1") = 77
> d.Value(9912) = "Whatever"
>
> if d.HasKey(9912) then print d.Value(9912)
>
> If you'd like a copy of the Framework source code for ideas, I can 
> provide it via personal e-mail.
>
> Paul R.
>
>
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