> From: Eric Iverson <[email protected]>
>
> An array of object values that 'often' to be dealt with as an array is
> perhaps best implemented as a normal J array that is a global class object.
> This can be referenced directly as an array and then in each of the objects
> the object value is the index into the class array and you use simple
> accessor funtions.
This could probably be illustrated with the Diagram
script, where there is an array of object item and
accessors to properties like Posistion, Name, Members, etc.
http://www.jsoftware.com/jwiki/Scripts/Diagram
ITEMS=: ,: 10 10;'Sample 1';<;:'one two'
ITEMS=: ITEMS,160 10;'Sample 2';<;:'three four five'
ITEMS=: ITEMS, 80 160;'Sample 3';<;:'six seven'
ITEMS=: ITEMS,250 160;'Sample 4';<;:'eight nine'
item_pos=: 3 : '(y,."1 0]0){::ITEMS'
item_setpos=:4 : 'ITEMS=:(<x)(<y,0)}ITEMS'
item_name=: 3 : '(y,1){::ITEMS'
item_membs=: 3 : '(y,2){::ITEMS'
item_memb=: 3 : '((({.y),2);{:y){::ITEMS'
NB. get connector positions
CONS=: 0 1,1 2,:1 3
... =. item_pos CONS
NB. find item by hit test
for_i. i.#ITEMS do.
P=. item_pos i
if. *./(P<M),M<P+IBSZ do.
...
end.
end.
> On Mon, Apr 20, 2009 at 12:49 PM, Matthew Brand wrote:
>
> > If I have a simple class such as:
> > coclass 'example'
> >
> > create =: 3 : ' X =: y'
> > destroy =: codestroy
> >
> > And I make a list of new objects:
> > n =.'example' (conew~)"(1 0) i.4
> >
> > n
> > +-+-+-+-+
> > |4|5|6|7|
> > +-+-+-+-+
> >
> > Then I can get at the X's inside each object like this:
> > X_4_
> > 0
> > X_5_
> > 1
> >
> > And like this:
> > v =. <":5
> > X__v
> > 1
> >
> > But how can I reconstruct the values of the X's from the list n?
> >
> > i.e., is there anything that looks like this?
> > (X__ )"0 n
> > 0 1 2 3
> >
> > Presumably the code to call a method on each object would look the same?
> >
> > I.e if there was a method: getX =: 3 : 'X'
> >
> > then calling it would look like?
> > (getx__ )"0 n
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> >
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