Dear Deepayan,
                              THanks for the pithy, pointed reply.

But isn't it risky? Can I somehow get a warning when x is not defined in the 
global environment but takes on a value from one of the loaded packages? any 
packages for that?

THanking you,
Yours sincerely,
AKSHAY M KULKARNI
________________________________
From: Deepayan Sarkar <deepayan.sar...@gmail.com>
Sent: Tuesday, April 4, 2023 7:51 PM
To: akshay kulkarni <akshay...@hotmail.com>
Cc: R help Mailing list <r-help@r-project.org>
Subject: Re: [R] on lexical scoping....



On Tue, Apr 4, 2023 at 7:26 PM akshay kulkarni 
<akshay...@hotmail.com<mailto:akshay...@hotmail.com>> wrote:
Dear Members,
                             I have the following code typed at the console 
prompt:

y   <-   x*10

X has not been defined and the above code throws an object not found error. 
That is, the global environment does not contain x.

That is not the correct interpretation of the error. R will happily evaluate

y   <-   pi*10

even if the global environment does not contain pi. The "environments" where R 
will look is given by

search()

If you manage to find a package that defines 'x' (and exports it), attaching it 
will put the package on the search path, and then your call will indeed no 
longer give an error.

-Deepayan

Why doesn't it look further in the environment stack, like that of packages? 
There are thousands of packages that contain the variable named  x. Of course, 
that happens if the above code is in a function (or does it?).

What concept of R is at work in this dichotomy?

THanking you,
Yours sincerely,
AKSHAY M KULKARNI

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