asterisk users - Sep 2005 - Unexpected results with "While" and "EndWhile" applications

I seem to be having a conceptual problem with the "While" and 
"EndWhile" applications.  It seems that on the first cycle, even if 
the result of the "While" is false that the enclosed applications 
will get run.  Is this expected?  It seems to be counter-intuitive, 
but I don't know what the intent of the While routines is.  I could 
of course put a "GotoIf" before the While loop to check to ensure 
that the first expression is true before entry into the While loop, 
but that seems redundant and ugly since the while point of While and 
EndWhile is to avoid the inelegance of GotoIf, I thought.

If anyone can't come up with a better explanation, I'll open a ticket 
on this but I'd like to first make sure that this behavior is not 
expected.


exten => 2231,1,Set(staticnumber=0)
exten => 2231,n,Set(counter=1)
exten =>
2231,n,While($["${counter}"<"${staticnumber}"])
exten => 2231,n,NoOp("This part of the code should never run!")
exten => 2231,n,Set(counter=$[${counter}+1])
exten => 2231,n,EndWhile
exten => 2231,n,NoOp("This part of the code should be the only thing 
that gets run!")


Console output from dialing 2231:

     -- Executing Set("SIP/2203-c134", "staticnumber=0") in
new stack
     -- Executing Set("SIP/2203-c134", "counter=1") in new
stack
     -- Executing While("SIP/2203-c134", "0") in new stack
     -- Executing NoOp("SIP/2203-c134", ""This part of the
code should
never run!"") in new stack
     -- Executing Set("SIP/2203-c134", "counter=2") in new
stack
     -- Executing EndWhile("SIP/2203-c134", "") in new stack
     -- Executing NoOp("SIP/2203-c134", ""This part of the
code should
be the only thing that gets run!"") in new stack
*CLI> show version
Asterisk CVS HEAD built by root@some.host.com on a i686 running Linux 
on 2005-09-03 23:27:34 UTC

JT

On 9/5/05, John Todd <jtodd@loligo.com> wrote:
> 
> I seem to be having a conceptual problem with the "While" and
> "EndWhile" applications.  It seems that on the first cycle, even
if
> the result of the "While" is false that the enclosed applications
> will get run.  Is this expected?  It seems to be counter-intuitive,
> but I don't know what the intent of the While routines is.  I could
> of course put a "GotoIf" before the While loop to check to ensure
> that the first expression is true before entry into the While loop,
> but that seems redundant and ugly since the while point of While and
> EndWhile is to avoid the inelegance of GotoIf, I thought.
> 
> If anyone can't come up with a better explanation, I'll open a
ticket
> on this but I'd like to first make sure that this behavior is not
> expected.
> 
> 
> exten => 2231,1,Set(staticnumber=0)
> exten => 2231,n,Set(counter=1)
> exten =>
2231,n,While($["${counter}"<"${staticnumber}"])
Put A space around the < operator, like this
exten => 2231,n,While($["${counter}" <
"${staticnumber}"])
This should help it.
> exten => 2231,n,NoOp("This part of the code should never
run!")
> exten => 2231,n,Set(counter=$[${counter}+1])
> exten => 2231,n,EndWhile
> exten => 2231,n,NoOp("This part of the code should be the only
thing
> that gets run!")
> 
> 
> Console output from dialing 2231:
> 
>      -- Executing Set("SIP/2203-c134",
"staticnumber=0") in new stack
>      -- Executing Set("SIP/2203-c134", "counter=1") in
new stack
>      -- Executing While("SIP/2203-c134", "0") in new
stack
>      -- Executing NoOp("SIP/2203-c134", ""This part of
the code should
> never run!"") in new stack
>      -- Executing Set("SIP/2203-c134", "counter=2") in
new stack
>      -- Executing EndWhile("SIP/2203-c134", "") in new
stack
>      -- Executing NoOp("SIP/2203-c134", ""This part of
the code should
> be the only thing that gets run!"") in new stack
> *CLI> show version
> Asterisk CVS HEAD built by root@some.host.com on a i686 running Linux
> on 2005-09-03 23:27:34 UTC
> 
> JT
> _______________________________________________
> --Bandwidth and Colocation sponsored by Easynews.com --
> 
> Asterisk-Users mailing list
> Asterisk-Users@lists.digium.com
> http://lists.digium.com/mailman/listinfo/asterisk-users
> To UNSUBSCRIBE or update options visit:
>    http://lists.digium.com/mailman/listinfo/asterisk-users
>