[R] terminology for frames and environments

[Peter Dalgaard]

Gabor Grothendieck <ggrothendieck at myway.com> writes:

> Thomas Lumley <tlumley <at> u.washington.edu> writes:
> 
> > The distinction between "environment" and "frame" is important. The frame
> > is what you find things in with get(, inherits=FALSE) and the environment
> > uses get(, environment=TRUE).
> 
> The thing I find odd about this one is that if we have:
> 
> e <- new.env()
> e$x <- 1
> f <- new.env(parent=e)
> f$x  # gives an error

(Actually not. I get NULL)


> then I would have expected x to be returned since f is an environment
> and x is in that environment.  On the other hand, if an environment
> is defined to be the same as a frame (and there is some other word for 
> an environment and its ancestors) then the above notation makes sense.

Why?  f$x is documented to be basically equivalent to
get("x",f,inherits=FALSE). In contrast,

> evalq(x,f)
[1] 1

works fine.

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
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