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Re: RE: Unexpected behaviour of HoldRest

• To: mathgroup at smc.vnet.net
• Subject: [mg45762] Re: [mg45738] RE: Unexpected behaviour of HoldRest
• From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
• Date: Sat, 24 Jan 2004 00:36:14 -0500 (EST)
• References: <200401230815.DAA27634@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

On 23 Jan 2004, at 08:15, Rolf Mertig wrote:

>> (unless it had the SequenceHold or HoldAllComplete attribute, but it 
>> has
>> neither of them)
> Which is very unfortunate, and it has been suggested in the past that 
> SequenceHold
> should be added to If.
> Until this suggestion hopefully gets realized
> in a future Mathematica version I use work-arounds like:
>
> ReleaseHold[If[1 == 1, Hold[Sequence][], 2]]
>
> Cheers,
>
> Rolf Mertig
> Mertig Consulting
> http://www.mertig.com
>
>
>
I wonder why you feel you need it since:


ReleaseHold[If[1 == 1, Hold[Sequence][], 2]]


Sequence[]


and


ReleaseHold[If[1 == 1, Hold[], 2]]


Sequence[]



Andrzej Kozlowski
Chiba, Japan
http://www.mimuw.edu.pl/~akoz/

• References:
  • RE: Unexpected behaviour of HoldRest
    • From: "Rolf Mertig" <rolf@mertig.com>