[R] as.character(quote(x$y) ) = "$" "x" "y" not "x$y"?

[peter dalgaard]

On 10 May 2014, at 12:54 , Duncan Murdoch <murdoch.duncan at gmail.com> wrote:

> On 10/05/2014, 6:46 AM, Barry Rowlingson wrote:
>> On Fri, May 9, 2014 at 10:42 PM, Hadley Wickham <h.wickham at gmail.com> wrote:
>>> Beware of the is.* functions:
>>> 
>>> * is.object() does not test the usual definition of objects
>>> * is.vector() does not test the usual definition of vectors
>>> * is.numeric() does not work the same way as is.character() or is.integer()
>>> * is.Date() doesn't exist
>>> * is.nan() doesn't return TRUE for some NaNs
>> 
>>  Can we have an "is.is" function that tells us these things?
>> 
>>  > is.is(is.object)
>>    [1] FALSE
>>     Warning: is.object() does not test the usual definition of objects
>> 
>>  > is.is(is.is)
>>    [1] TRUE
>> 
>>  For further exploration, demo("is.things") creates a handy "is.ALL"
>> function that outputs the result of running a lot of is.X functions on
>> its argument.
> 
> I tried to write it, but the trouble is, is.is(is.is) is FALSE.
> 
> Duncan


Worse,

is.is(mybaby) | is.aint(mybaby)

comes out TRUE whatever the value of mybaby.

-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com