Re: How can one produce the unevaluated effect that Mathematica uses on SetOptions and certain Integrate commands?
- To: mathgroup at smc.vnet.net
- Subject: [mg71811] Re: How can one produce the unevaluated effect that Mathematica uses on SetOptions and certain Integrate commands?
- From: "Chris Chiasson" <chris at chiasson.name>
- Date: Thu, 30 Nov 2006 06:05:00 -0500 (EST)
- References: <acbec1a40611290301j270221e3x40b39b718f83d516@mail.gmail.com>
Let me guess. This is done with some kind of option checking and/or a
partial evaluation technique.
On 11/29/06, Chris Chiasson <chris at chiasson.name> wrote:
> See Output 4. There is no HoldForm present. I want to know how to
> shield things from the evaluator so that I am able to return the input
> (exactly as given). Thank you.
>
> In[1]:=
> System`Dump`$MessagesInHelpBrowserAreKnown=False;
> debug`f[blah_]:=Unevaluated[debug`f[blah]]
> debug`f[1]
> From In[1]:=
> $IterationLimit::itlim: Iteration limit of 4096 exceeded.
>
> Out[3]=
> Hold[debug`f[1]]
>
> In[4]:=
> SetOptions[Plot3D,{AmbientLight\[Rule]None,AspectRatio\[Rule]1}]//FullForm
>
> From In[4]:=
> SetOptions::rep: {AmbientLight\[Rule]None,AspectRatio\[Rule]1} is not a valid \
> replacement rule.
>
> Out[4]//FullForm=
> SetOptions[Plot3D,List[Rule[AmbientLight,None],Rule[AspectRatio,1]]]
>
> --
> http://chris.chiasson.name/
>
--
http://chris.chiasson.name/