On Tue, Jul 26, 2011 at 11:58 PM, Tim Cowlishaw wrote:
> On Tue, Jul 26, 2011 at 11:14 PM, Alexander Solla
> wrote:
>
> > data OrderType = Market Size | Limit LimitPrice Expiration Size | Stop
> > (Either Percent Price)
> > newtype Sell = Sell OrderType
> > newtype Buy = Buy OrderType
> > newtype
On Tue, Jul 26, 2011 at 11:14 PM, Alexander Solla wrote:
> data OrderType = Market Size | Limit LimitPrice Expiration Size | Stop
> (Either Percent Price)
> newtype Sell = Sell OrderType
> newtype Buy = Buy OrderType
> newtype Order = Order (Either Buy Sell)
> size :: Order -> Int
> size (Order
On Tue, 26 Jul 2011, Tim Cowlishaw wrote:
For instance, for a typeclass representing the interface that any
Order type should implement:
class Order o where
price :: o -> Int
size :: o -> Int
I'd like to be able to specify an Eq instance for all types of class
Order in a manner similar to t
On Tue, Jul 26, 2011 at 1:52 PM, Tim Cowlishaw wrote:
> On Tue, Jul 26, 2011 at 7:46 PM, Evan Laforge wrote:
>
> > Could you give a specific example of the problem you're trying to solve?
>
> Sorry, yes, that'd be useful :-)
>
> So, the project I'm working on involves developing a simulation of a
On Tue, Jul 26, 2011 at 7:46 PM, Evan Laforge wrote:
> Could you give a specific example of the problem you're trying to solve?
Sorry, yes, that'd be useful :-)
So, the project I'm working on involves developing a simulation of a
securities market. I have a type which models an order book, on w
> However, I'd be curious to know if (a) There are better or more
> idiomatic ways of achieving the same effect, and (b) Whether or not I
> should be doing this at all; It did occur to me that this seems rather
> trying to re-implement OOP-style inheritance with typeclasses, and
> therefore perhaps
For:
instance (Ord a) => Max a where
maximum = max
The same could more simply be achieved with a function:
maximum :: Ord a => a
maximum = max
Now, you probably wanted both a base-case using max and type specific,
special cases:
instance Max Int where
maximum = 2^16
If you have both instan
Hi all,
I'm currently embarking on my first major project in Haskell, after
dabbling with it for several years, and seem to keep finding myself in
situations where I create a typeclass that seems to be some sort of
specialisation of another, more general typeclass. Given that this is
the case, I'v
