Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2006
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2006

[Date Index] [Thread Index] [Author Index]

Search the Archive

RE: Context

  • To: mathgroup at smc.vnet.net
  • Subject: [mg70985] RE: [mg70956] Context
  • From: "Virgilio, Vincent - SSD" <Vincent.Virgilio at itt.com>
  • Date: Fri, 3 Nov 2006 01:39:40 -0500 (EST)

Likely the current context doesn't change until the end of the current
expression (similar to the play between side-effects and sequence points
in C/C++).

Below, a CompoundExpression[] contains a Begin[].  I think the Begin[]
will not affect anything in that CompoundExpression[]. So Mathematica
creates t in Global` rather than x`, which you see.

I don't know how to draw a line between parsing and execution in
Mathematica. Perhaps it could be done in terms of the documented
evaluation process. There's been some talk on this lately, I think about
Format[]. Anyone care to elaborate?

Vince Virgilio


-----Original Message-----
From: dh [mailto:dh at metrohm.ch] 
To: mathgroup at smc.vnet.net
Subject: [mg70985] [mg70956] Context


Hello,

consider:

fun[x_]:=( Begin[x];

       Print[t];

       End[];

       );

according to the manual one would think that the variable t in context x


is printed. However, this is wrong! What is printed is Global`t. 

Therefore, the context to which a symbol belongs is determined during 

parsing and NOT execution.

Can anybode give more insight and strict rules for this quirck?

Daniel


************************************
This e-mail and any files transmitted with it are proprietary and intended solely
for the use of the individual or entity to whom they are addressed. If you have
received this e-mail in error please notify the sender. Please note that any views
or opinions presented in this e-mail are solely those of the author and do not
necessarily represent those of ITT, Inc. The recipient should check
this e-mail and any attachments for the presence of viruses. ITT accepts
no liability for any damage caused by any virus transmitted by this e-mail.
************************************



  • Prev by Date: Re: Mathematica / MacOSX / XDarwin fonts problem
  • Next by Date: Re: Context
  • Previous by thread: Re: Context
  • Next by thread: Re: RE: Context