]
Sent: Fri 11/01/2008 18:03
To: Nicholls, Mark
Cc: haskell-cafe@haskell.org
Subject: Re: [Haskell-cafe] type questions again
On Jan 11, 2008 5:47 PM, Nicholls, Mark [EMAIL PROTECTED] wrote:
If you wrap an existential type up in a constructor, not
much changes:
If you wrap a what
2008/1/11 Nicholls, Mark [EMAIL PROTECTED]:
Can someone explain (in simple terms) what is meant by existential and
universal types.
Preferably illustrating it in terms of logic rather than lambda calculus.
Well, I don't know about logic. While they are certainly related to
existential and
On 11/01/2008, Nicholls, Mark [EMAIL PROTECTED] wrote:
Preferably illustrating it in terms of logic rather than lambda calculus.
There's plenty of stuff out there on it….but most of it seems double dutch
(no offense to the dutch intended).
I think the preferred idiom, considering the
On Jan 11, 2008 5:47 PM, Nicholls, Mark [EMAIL PROTECTED] wrote:
If you wrap an existential type up in a constructor, not
much changes:
If you wrap a what?should this read existential or universal?
Whoops, right, universal.
newtype ID = ID (forall a. a - a)
ID can hold any value
-Original Message-
From: Luke Palmer [mailto:[EMAIL PROTECTED]
Sent: 11 January 2008 17:11
To: Nicholls, Mark
Cc: haskell-cafe@haskell.org
Subject: Re: [Haskell-cafe] type questions again
2008/1/11 Nicholls, Mark [EMAIL PROTECTED]:
Can someone explain (in simple terms
