[Rd] Bug in new() or validObject() in methods package (PR#7922)

Peter Dalgaard p.dalgaard at biostat.ku.dk
Mon Jun 6 22:55:16 CEST 2005


murdoch at stats.uwo.ca writes:

> Is it doing an extra eval or something?  It looks like it:
> 
>  > x <- expression()
>  > x
> expression()
>  > eval(x)
> NULL
>  >
>  > x <- quote(expression())
>  > x
> expression()
>  > eval(x)
> expression()
>  > eval(eval(x))
> NULL

You do realize that the two expression() results are not identical:

> x <- quote(expression())
> class(x)
[1] "call"
> x <- expression()
> class(x)
[1] "expression"

Not that I can fathom what bearing that has on the real problem...

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)             FAX: (+45) 35327907



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