[EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] On Behalf Of Larry Evans
> Sent: 18 October 2008 10:48 pm
> To: haskell-cafe@haskell.org
> Subject: [Haskell-cafe] Re: Is there already an abstraction for this?
>
> On 09/23/08 01:01, Jake Mcarthur wrote:
> > -BEGIN PGP SIGNE
On 09/23/08 01:01, Jake Mcarthur wrote:
> -BEGIN PGP SIGNED MESSAGE-
> Hash: SHA1
>
> The first thing I thought of was to try to apply one of the recursion
> schemes
> in the category-extras package. Here is what I managed using
catamorphism.
>
> - - Jake
>
> -
>
---
Jeremy Shaw wrote:
> I have an expression data-type:
>
>> data Expr
>>= Quotient Expr Expr
>>| Product Expr Expr
>>| Sum Expr Expr
>>| Difference Expr Expr
>>| Lit Double
>>| Var Char
>> deriving (Eq, Ord, Data, Typeable, Read, Show)
I prefer such expressions written
