[Haskell-cafe] IO and Wash
jgoerzen at complete.org
Wed Feb 16 10:51:50 EST 2005
On Wed, Feb 16, 2005 at 02:56:11PM -0000, Simon Marlow wrote:
> > the unsafe_io prevent that?
> You can avoid lots of unnecessary state-saving by judicious use of
> WASH's 'once' function. eg.
Hmm. I have tried this, but I'm not seeing any change in the amount of
saved state as a result of using once.
For instance, I have a selection screen. People can select things
there, then go off and do things. At various points, the user could
realize they made the wrong selection, so I call the selection screen
again. However, even though I have once $ standardQuery $ ... in the
selection screen, all that state is saved...
I don't think I can use forever there either, because I'm using that
trick (which does seem to work) to enable returning to a yet earlier
Maybe I'm missing what once does.
Thanks again for your help.
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