[R] R and Scheme

[Wacek Kusnierczyk]

Luke Tierney wrote:
> On Tue, 9 Dec 2008, Wacek Kusnierczyk wrote:
>
>> Stavros Macrakis wrote:
>>>
>>> R does not have continuations or call-with-current-continuation or
>>> other
>>> mechanisms for implementing coroutines, general iterators, and the
>>> like.
>>>
>>
>> there is callCC, for example, which however seems kind of obsolete.
>
> There is nothing obsolete about it.  It supports only downward or
> dynamic extent continuations and so is not useful (nor intended) for
> the things Stavros mentions.  It is useful for escaping from deeply
> nested function calls, for example recursive examination of tree
> structures -- that is why it exists.  At some point upward (at least
> one-shot) contitnuations may be added as well, but probably not soon.
>
> luke

ok, thanks for the explanation.

vQ