On 02/03/07, Bayley, Alistair
There's a big difference between getContents and Takusen: getContents has a non-trivial implementation (using unsafeInterleaveIO) that allows it to return data lazily. Takusen has no such implementation.
... ie, there's deep dark magic involved in the seemingly simple getContents, which isn't easily available to mere mortals (or even semi-immortal library designers). That figures. It's a shame, but not totally unsurprising.
That's what my earlier code looked like, and I found it harder to understand than the getContents/process/put approach. I'm trying to explore ways of factoring data manipulation code out of database access functions, but maybe that's not the right way of doing it.
I don't think it's possible to pursue this style of programming with Takusen. If you do, you'll have to process the entire result-set into a data structure and then process it, which has obvious memory implications.
Oh, well. It's mostly irrelevant for me anyway, as the data sets I'm actually playing with are small enough that slurping them into memory isn't an issue - so I just choose between a simple and decoupled implementation or a more complex and scalable one, which is a fairly standard optimisation choice. Thanks for clarifying. Paul.