[Haskell-cafe] Re: A bit of a shock - Memoizing functions

Hi Dan, yep, I've come across that one too and wouldn't you know it, the by now infamous Luke Palmer has left an interesting insight on that blog too :). So I reckon here the cycle closes. Günther Dan Piponi schrieb:

2009/3/27 Kirk Martinez :

...

I wonder: does the converse exist? Haskell data constructors which are really functions? How and for what might one use those?

You might enjoy reading about the use of tries for memoisation. Conal Elliott explains nicely how you can an isomorphism between certain types of function and certain types of tree structure: http://conal.net/blog/posts/elegant-memoization-with-functional-memo-tries/

It's neat because the rules for constructing the isomorphism are just like some well known rules of high school algebra, but interpreted in a new way. -- Dan