R help - Mar 2010 - "is" and the story of a typo

Hi all,
The gurus may pour scorn on me for not knowing this, but I happened to 
mistype "if" as "is" in the heat of debugging a function. As
I scanned
the debugged function with some satisfaction, I noticed the error. How 
could this have worked? I assume that "is" is a generic function that 
calls one of the is.* functions to evaluate whatever is passed. It 
appears that this particular typo causes "is" to work out and report
the
contents of its argument. Ho hum. As I did not test the FALSE result, I 
never would have noticed that it was not the conditional statement I 
expected until it evaluated something that should have been FALSE.

Jim

On 30-Mar-10 23:23:09, Jim Lemon wrote:
> Hi all,
> The gurus may pour scorn on me for not knowing this, but I happened
> to  mistype "if" as "is" in the heat of debugging a
function. As I
> scanned the debugged function with some satisfaction, I noticed the
> error. How could this have worked? I assume that "is" is a
generic
> function that calls one of the is.* functions to evaluate whatever
> is passed. It appears that this particular typo causes "is" to
work
> out and report the contents of its argument. Ho hum. As I did not
> test the FALSE result, I never would have noticed that it was not
> the conditional statement I expected until it evaluated something
> that should have been FALSE.
> 
> Jim
Hi Jim,

  is: ?is

  is(is)

  is(is(is))

  is(is(is(is)))

  identical(is(is(is)),is(is(is(is))))

Ted.

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Date: 31-Mar-10                                       Time: 09:21:29
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