[plt-scheme] Scheme and R

From: Eli Barzilay (eli at barzilay.org)
Date: Fri Mar 27 02:34:52 EDT 2009

On Mar 26, Prabhakar Ragde wrote:
> Neil Toronto wrote:
> 
> > Back to lexical scope. To get around = creating bindings and how
> > that makes it difficult to mutate outer scope variables, R has a
> > special assignment operator <<- that operates on the nearest outer
> > scope. It also creates bindings there if they don't already
> > exist. It's like Python's "global" but for any level. Funky.
> 
> There's something weird going on with scope in "lazy evaluation" in
> R.  It's not lexical, but dynamic, and it's not clear to me when it
> flips from one to the other.

IIUC, it looks like it's possible to implement with a not too hard
macro.

-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                  http://www.barzilay.org/                 Maze is Life!


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