[Rd] proto and baseenv()

Gabor Grothendieck ggrothendieck at gmail.com
Thu Feb 25 18:36:24 CET 2010

On Thu, Feb 25, 2010 at 9:57 AM, hadley wickham <h.wickham at gmail.com> wrote:
>> Presumably if I ask for p$a or p$b later, it's because I'm interesting
>> in the value of "p$a" or "p$b" that I specifically put inside that
>> environment.  Otherwise I would just ask for "a" or "b".  If I'm
>> asking for "p$b" it the above case, that means I forgot to declare b
>> inside p.  In this case there should be an error telling me that, not
>> a silent substitution of the wrong quantity.
>> If someone wanted to do the y$ls() thing, they could always
>>> y <- proto(a=1)
>>> with(y, ls())
>> [1] "a"
>> Another reason is that there are plenty of other programming languages
>> that have similar structures and this behavior is very odd.  In
>> standard languages asking for "b" inside the "p" object gives you an
>> error, and no one complains.
> You might want to have a look at the mutatr package which implements
> prototype OO with the behaviour you're looking for (I think).  I also
> have a paper available if you email me off list.

I think his objection is really only that he must specify baseenv() to
get the behavior he prefers but from what I understand (I am basing
this on my understanding that mutatr works like io language) in mutatr
one must use Object which seems really no different.

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