[Haskell-cafe] To yi or not to yi, is this really the question? A plea for a cooperative, ubiquitous, distributed integrated development system.

Bayley, Alistair Alistair_Bayley at invescoperpetual.co.uk
Thu Jun 21 05:27:41 EDT 2007

> [mailto:haskell-cafe-bounces at haskell.org] On Behalf Of Tomasz Zielonka
> > On Mon, Jun 18, 2007 at 10:05:40PM +0100, Pasqualino 
> 'Titto' Assini wrote:
> > > Most languages, even Java, have a reflection capability 
> to dynamically
> > > inspect an object.
> > 
> > > It is surprising that Haskell doesn't offer it.
> I'll just add that I've never consciously used reflection, so 
> I probably
> overlook some features of Haskell that give a part of reflection
> functionality.

On the surface, Haskell would appear to not offer reflection. However,
you can get quite a long way with Data.Generics and Data.Dynamic, and
deriving (Typeable, Data), which will give you introspection of data
types. Here's a nice little article on using deriving Data:


And the hs-plugins library will give you dynamic loading, but I don't
think there's any introspection capability (yet?)

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