Weirdness Passing Messages
dburgun at dsl.pipex.com
Fri Mar 24 11:43:43 EST 2006
On 24 Mar 2006, at 16:12, J. Landman Gay wrote:
> David Burgun wrote:
>> Incidentally, the above works just fine regardless of the stack/
>> card/ object using "put <something> into me". The problem I
>> described yesterday was brought to light because when a new
>> folder is selected, I wanted to select the first line (file) in
>> the list, so inside ISM_FolderSelect(), I did a ISMPutMessage
>> ("ISM_FileSelected, kFileKind, line 1 of me), when this happened,
>> "me" in the receiving handler got Beswick'ed!
> Which is reasonable, I think. Think about this a moment --
> parameters are always evaluated before being passed. When you pass
> "me" in a parameter, the "me" will refer to the object currently
> executing the script, not the target object the script will
> eventually refer to later. This is normal behavior.
This was just short hand to explain how I came to find the bug. What
I was trying to point out is that the problem was triggered by me
calling a handler in an unopened card from an object inside the same
The actual code is:
put line 1 of the text of me into myFileName
get ISMPutMessage(ISM_FileSelected, kFileKind, myFileName)
The problem was in the ISM_FIleSelected handler in the *destination"
object. Which did this:
on ISM_PutMessage( heMessageID,theSubCode,theFilePathName)
-- Other code
put <something> into me --<something> being based on the file name.
-- Other code
> Take this example:
> addNums (1+1)
> The addNums handler will receive a parameter of "2", not "1+1".
> Ditto for "me", which will be interpreted as the object *currently*
> running the script, not the future target of the handler reference.
I don't pass "me" as a parameter for the very reason you mention. The
problem is in the destination handler which is a different "me"!!!!!
> When passing a reference parameter, use an ID or other static
> reference, not "me" which is always subject to interpretation. As
> you found out. ;)
> If you absolutely must use "me" then you can try putting the
> parameter in quotes to force it into acting as a string. Strings
> won't be evaluated. I don't know if this will work in your
> situation but you can try it.
> Now that I understand your usage better, I do not think this is a bug.
The bug is that:
put <something> into me
set the text of me to <something>
Doesn't work 100% of the time. Sorry for the confusion, I didn't mean
you to take the pseudo code I posted literally. I have found the bug
now and changed the offending lines to:
set the text of the long is of me to <something> and it works fine now.
Thanks a lot
All the Best
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