Lennart Augustsson wrote:
We don't need them [existentials] from a theoretical perspective,
but in practice I'd rather use existentials than encodinging them
in some tricky way.
If the claim that we don't need existentials theoretically is obvious,
I don't have the argument. Still,
Yes, hbc had existential types around 1993.
I've used an encoding of existentials in O'Caml (well F#), and it
works, but I find it painful.
And when a very smart but non-CS person saw it his mind boggled,
whereas he understood the existential version just fine.
On Thu, Oct 16, 2008 at 8:26 AM,
Yes, hbc had existential types around 1993.
I've used an encoding of existentials in O'Caml (well F#),
and it works, but I find it painful.
And when a very smart but non-CS person saw it his mind
boggled, whereas he understood the existential version just fine.
I'm a CS person, and when
Lennart Augustsson wrote:
I was just pointing out that the mechanism for doing the OO thing
exists in Haskell too, albeit looking a little different.
Indeed there is a mechanism for doing OO in Haskell -- several of
them. Most of them have nothing to do with Existentials. In the
OHaskell
On Wed, Oct 15, 2008 at 6:05 AM, [EMAIL PROTECTED] wrote:
Regarding existentials, the web page
http://okmij.org/ftp/Computation/Existentials.html
demonstrates how to systematically eliminate existentials. In fact,
the object encoding via existentials can be easily transformed into
What do you mean by need? From a theoretical or practical perspective?
We don't need them from a theoretical perspective, but in practice I'd
rather use existentials than encodinging them in some tricky way.
On Wed, Oct 15, 2008 at 11:05 AM, [EMAIL PROTECTED] wrote:
The web page
begs a
re: the importance of existential-cleansing
On the one hand, it's easy to concur that existentials are simpler
than the alternatives, the tortuous elimination of CC Shan's
translucent existential being a case in point.
And it's also easy to dismiss such caprice as a penchant for Houdinian
