[R] Question about <<- assignment

[Peter Dalgaard]

Duncan Murdoch wrote:

> <<- doesn't need to find z.  It will replace it if found, or create a 
> new one if not.  (Personally I would have limited that to the first 
> case, i.e. it should fail if it doesn't find z.)
>

Possibly. It's a holdover from S, where <<- assigns to the global 
environment unconditionally.  (S doesn't have lexical scope, so there 
are effectively only two places to choose from: the function evaluation 
frame and the global frame -- unless you start mucking around with 
sys.frame, frame 0, frame 1, etc., in which case you'd use assign(...))


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