How does a command find out who called it?

[Richard Gaskin]

Bob Sneidar wrote:

 > Dispatch does not have an "in time" argument. Only send does.
 > The other difference is that send temporarily changes the
 > defaultStack to the one containing the called handler. Any
 > references to "this card" or "this stack" will reference the
 > target stack, not the stack the handler was called from.
 > Dispatch does not do this. It can be a gotcha if you are not
 > aware of it.

Are you thinking of "call"?

I just ran this test:

1. Make a new stack "aaa", and name the card "aaaaaaaaa"

2. Make a new stack "bbb", and name the card "bbbbbbbbb"

3. Add a button to "bbb" with this script:
     on foo
       put the name of this cd
     end foo

4. Click stack "aaa" to bring it to the front

5. Run these in the Message Box

      send "foo" to btn 1 of stack "bbb"
      RESULT:   card "bbbbbbbbb"

      dispatch "foo" to btn 1 of stack "bbb"
      RESULT:   card "bbbbbbbbb"

      call "foo" of btn 1 of stack "bbb"
      RESULT:   card "aaaaaaaaa"


Interestingly, a similar test using different cards in the same stack 
yields a different result:

1. Make a stack with two cards, one named "aaa" and the other "bbb"

2. On card "bbb" add a button with the "foo" handler above

3. Go to card 1 ("aaa") and run these in the Message Box:

     send "foo" to btn 1 of cd "bbb"
     RESULT: card "aaa"

     dispatch "foo" to btn 1 of cd "bbb"
     RESULT: card "aaa"

     call "foo" of btn 1 of cd "bbb"
     RESULT: card "aaa"


Should we expect "send" and "dispatch" to switch context with the card 
reference?

--
  Richard Gaskin
  Fourth World
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