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Re: HoldAll

• To: mathgroup at smc.vnet.net
• Subject: [mg66577] Re: HoldAll
• From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
• Date: Sat, 20 May 2006 04:48:08 -0400 (EDT)
• References: <e4jukh$d94$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

Hi,

because HoldAll hinder the evaluation of the function
*arguments* but not the evaluation of the function itself.

Regards
   Jens

umrakmm at cc.umanitoba.ca wrote:
> Hello to everyone
> 
> Quick question with regards to why the HoldAll attribute no longer works once 
> you define the function.  For example, before the definition, it serves the 
> purpose it was meant to serve:
> 
> Input
> Clear[ff]
> SetAttributes[ff, HoldAll]
> ff[1, 2, 3 + 4]
> 
> Output
> ff[1, 2, 3 + 4]
> 
> But once I actually assign the "functional guts", it doesn't do what it did 
> above:
> ff[x_, y_, z_] := x + y + z;
> ff[1, 2, 3 + 4]
> 
> 10
> 
> Why?
> 
> Thanks to all
> MR
> 
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