[Haskell-cafe] File path programme

Malcolm Wallace Malcolm.Wallace at cs.york.ac.uk
Wed Jan 26 09:29:49 EST 2005

Keean Schupke <k.schupke at imperial.ac.uk> writes:

> >So let's define a new algebraic datatype something like:
> I think you can guess what comming - why not use a class for extensibility:
>     class Path p where ...
> The path class would provide all the operations for using paths...

Yup, good idea, and I think this would also allow David Roundy's
suggestion of a FastString implementation of filepaths - it becomes
just another instance.

> This has the advantage that people can add instances for platforms 
> without having to alter the code in the library...

Exactly.  Yes.


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