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<== Date ==> <== Thread ==>

Subject: Re: question about state notation language logic for when() with delay
From: Benjamin Franksen <benjamin.franksen@helmholtz-berlin.de>
To: <tech-talk@aps.anl.gov>
Date: Wed, 10 Aug 2011 20:06:38 +0200
Hi Jay

Ron answered your question correctly, so let me just add that this is
documented in the (new) manual; quoting from http://www-
csr.bessy.de/control/SoftDist/sequencer/Reference.html#delay:

 boolean delay(double delay_in_seconds)

 Returns whether the specified time has elapsed since entering the state. It
 should be used only within a when expression.

Am Mittwoch, 10. August 2011, um 19:00:51 schrieb Chestnut, Ronald P.:
> The timer starts when the state containing the when clause is entered.
> There are some flags which determine if it restarts when the state loops
> back to itself or not.
>
> So the order of elements in the when expression is irrelevant.

With respect to the position of  delay()  calls this is true, but in general
the order may of course be relevant, for instance in

  when(a > 0 && 1/a > b)

Evaluation of expressions proceeds exactly as in C, including the order of
side-effects. (It is, however, recommended to use only effect-free expressions
in  when()  clauses.)

Cheers
Ben

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Replies:
RE: question about state notation language logic for when() with delay Jay Steele
References:
question about state notation language logic for when() with delay Jay Steele
Re: question about state notation language logic for when() with delay Chestnut, Ronald P.

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