I think the real complication in the use of IT is less in its scoping than
in the fact that it's kind of a garbage variable that the system uses in
ways that aren't always predictable. Some operations return a value in IT
and others return a value in the result and, IIRC, sometimes you can get one
answser in IT and a different one in the result.

When I wrote my original book on HyperTalk, I said, among other things, "be
careful when using It in your scripts. Typically, you will use this special
variable when few, if any, commands appear between the time you put a value
into the variable and the time you need that variable."

As far as I know, the following Transcript commands place their results into
It (though there may be many others; this is the old HC list):

answer
ask
convert
get
read from file

(All variations of those as well.)

On 6/22/06, Jim Ault <[EMAIL PROTECTED]> wrote:

On 6/22/06 10:15 AM, "[EMAIL PROTECTED]" <[EMAIL PROTECTED]> wrote:

> My beef with IT is that IT isn't defined as a global variable by
default. For
> example, if you need a quick file path and type ...
>     answer file ""
> ... you can't get your path unless you previously did this ...
>     global it
> In HC that was done by default which I found to be very handy. And that
is
> all I have to say about IT.

I don't remember 'it' as being global by default in HCard.

The downside for using 'it' as a global is that any handler in any stack
or
message path could affect that value.  In particular,
the value of 'global it' is set in your handler,
then you navigate to another card,
and thus you may have triggered 'on closecard', 'on opencard', 'on
openstack', etc.

Of course, 'it' will be a local only, unless the script or handler
declares
global it
so any scripts you do not control will not regard 'it' as a global, such
as
library front/back scripts, plugins.

Try card script = global it, get "huckleberry"
then have the stack script use 'it' as normal, 'it' = empty

This is normal variable scoping in Rev, and I think HCard.



Jim Ault
Las Vegas


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