Simon Peyton-Jones schrieb:
| instance Show [Equation]
| where
| showsPrec _ eqs = certain program which prints a list of equation
| in a `nicer' way than by the default list
[...]
Perhaps. That's what I'd like feedback about. What do others think?
Overlapping
| What are the disadvantages of compiling every library
| with -fallow-overlapping-instances?
It's not H98, so it has to be an option, enabled by a flag. Of course
you are free to put the flag at the top of every module.
Sergey's point is that the libraries are pre-compiled, so you can't add
On Mon, Sep 04, 2006 at 03:39:06PM +0100, Simon Peyton-Jones wrote:
|
| data Equation = ...
| instance Show Equation where ...
|
| instance Show [Equation]
| where
| showsPrec _ eqs = certain program which prints a list of equation
|
On 9/5/06, Simon Peyton-Jones [EMAIL PROTECTED] wrote:
The old model was that every instance is potentially overlappable; andyou only need the flag when you *use* the instances.But peoplecomplained that the clients of their library should not need to knowimport Foogle and use
To my request on overlapping instances in 6.6 candidate
Simon Peyton-Jones [EMAIL PROTECTED] writes on
4 Sep 2006
[..]
GHC 6.6's story is that an instance declaration can only be overlapped
if you compile that module with -fallow-overlapping-instances. Since
the list instance for Show
|
| data Equation = ...
| instance Show Equation where ...
|
| instance Show [Equation]
| where
| showsPrec _ eqs = certain program which prints a list of equation
| in a `nicer' way than by the default list
printing
|
On Mon, Sep 04, 2006 at 06:22:34PM +0400, Serge D. Mechveliani wrote:
Here is an example of how I alayws was using overlaps with standard
instances.
data Equation = ...
instance Show Equation where ...
instance Show [Equation]
where
Simon Peyton-Jones wrote:
|
| data Equation = ...
| instance Show Equation where ...
|
| instance Show [Equation]
| where
| showsPrec _ eqs = certain program which prints a list of equation
| in a `nicer' way than by
Simon Peyton-Jones [EMAIL PROTECTED] schrieb im Newsbeitrag |
| This gives the user possibility to redefine a certain part of the
| library instance.
| Is not ghc-6.4.1 better at this point?
Perhaps. That's what I'd like feedback about. What do others think?
...
Simon
What are the
