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Re: ClearAll ?? or what

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  • Subject: [mg102835] Re: ClearAll ?? or what
  • From: Peter Breitfeld <phbrf at>
  • Date: Fri, 28 Aug 2009 05:43:48 -0400 (EDT)
  • References: <h7371j$b28$> <h75nba$p3g$> <h77nb8$s5d$>

To suppress globally the warning message, you may add the line


to your $UserBaseDirectory/Kernel/init.m  file.

AES wrote:

F> In article <h75nba$p3g$1 at>,
>  Armand Tamzarian <mike.honeychurch at> wrote:
>> Remove["Global'*"]
>> or
>> If[Length[Names["Global`*"]] > 0, Remove["Global`*"]];
>> so as to avoid the message of no Global symbols exist.
> The point here is that you might routinely put
>    Remove["Global'*"]
> as the first line in all of your freestanding notebooks, so that any 
> time you open a new notebook or edit something in an existing notebook, 
> then do a Select All and Enter to execute that notebook, you will have 
> something like a "clean start" for that execution.
> The problem (a minor one) is that if you do this, then the first time 
> you execute such a notebook in a newly opened Mathematica session, you 
> will get the "error" message:
>    Remove::rmnsm: There are no symbols matching "Global`*". >>
> I put "error" in quotes here because (a) so far as I can see you haven't 
> really damaged anything by doing this, and (b) this shouldn't be called 
> an error in any case, at least if you live by the standard computer 
> science wildcard convention that "the asterisk character ("*") 
> substitutes for any zero or more characters".
> The history is that doing this wasn't an error through several early 
> versions of Mathematica.  It became an error sometime around v4? 
> or v5?.  Why? -- who knows?
> The solution, so far as I can see, is to use
>    x; Remove["Global'*"]
> as the first line in all your notebooks.  Can this do any harm?

Peter Breitfeld, Bad Saulgau, Germany --

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