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Re: Sequential evaluation of lists

• To: mathgroup at smc.vnet.net
• Subject: [mg53187] Re: Sequential evaluation of lists
• From: "Ray Koopman" <koopman at sfu.ca>
• Date: Tue, 28 Dec 2004 06:30:38 -0500 (EST)
• References: <cqbhu8$4oe$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

Ray Koopman wrote:
> When I first started using Mathematica (v2), one of the features
> that I found rather surprising is its sequential evaluation of lists
> [...] so far I have found no exception to sequential evaluation
> and no mention of it in any documentation. Have I missed something?

Yes. In an offline message, DrBob wrote:

> In the Book, section 2.6.4, it's explained that Mathematica has a
> standard evaluation procedure:
>
> Evaluate the head of the expression.
> Evaluate each element in turn.
> .... other rules
>
> So yes, it appears that sequential evaluation is the basic rule --
> with exceptions when the Head has attributes HoldFirst or Orderless,
> etc.

The standard evaluation procedure is the same now as it was in v2 --
only the section number has changed.