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Re: More /.{I->-1} craziness

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  • Subject: [mg106529] Re: More /.{I->-1} craziness
  • From: AES <siegman at>
  • Date: Fri, 15 Jan 2010 03:20:47 -0500 (EST)
  • Organization: Stanford University
  • References: <> <hhhmn8$o9t$> <hhpl28$9lf$>

In article <hhpl28$9lf$1 at>,
 Leonid Shifrin <lshifr at> wrote:

> I stick to my view of replacement rules as being aimed primarily at advanced
> users, or at least as a tool that should be used with much care.  

But on the other hand, innumerable software apps of all varieties and at 
all levels down to the most elementary (e.g., nearly all word 
processors, text editors, graphics programs, spreadsheet programs, email 
programs, and so on) include "Find and Replace" capabilities.

These capabilities frequently have varied options:  
   "Find Next"  "Replace and Find"  "As Word"
   "Start at Top"  "Replace All"  "In Selection Only"
and so on.  Many have optional GREP abilities.


1)  Most any computer user at even a very elementary level knows about 
these tools, rather expects to have them available, and expects them to 
function as they in fact do function.

2)  In particular, they operate (visibly!) on what you see -- not some 
arcane internal representation.

3)  So, if such a novice user goes to Mathematica, it's only to be 
expected that this user will thnik that Mathematica's ReplaceAll should 
function in a similar fashion (and, helpfully, Mathematic's /. operator 
most of the time does function in that way) (sarcasm mode in that 

4)  So why can't Mathematica also have a TextReplace[ ] function, or 
something similar, that would function in that way _on what the user 
sees or has typed (or copied and pasted) into a selected cell_.

Given such a function my input would be Find " I " and replace it
with " (-I) ".

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