Sean, The answer is, I'm working on a recently semi-released package called TrieMap. The objective of this package, building off of the work in this paperhttps://docs.google.com/Doc?docid=0AWuaUF8ZNTNDZHB3emdyaF8zMzNmZmtmcHo2Yw&hl=en, is to automatically derive the type of a generalized trie for any algebraic type based on its algebraic representation. (I am working on writing up my methods for publication.) Of course, if I could get automatic access to the mechanisms of a type's constructors, I wouldn't even require users to describe the algebraic representation of their type... Louis Wasserman wasserman.louis@gmail.com On Tue, Sep 8, 2009 at 2:34 AM, Sean Leather wrote:

...

I don't know a thing about SYB, Data.Data, or Data.Typeable, mostly because I'm an efficiency fanatic. Nevertheless, I'd like to know whether or not there's a way to deconstruct a (mostly) arbitrary type, into tuples, unions, etc. using this framework. Any thoughts?

You can use the Template Haskell deriving in EMGM to get that structure pretty efficiently.

http://www.cs.uu.nl/wiki/GenericProgramming/EMGM http://hackage.haskell.org/package/emgm

The obligatory question is: why do you want it?

Sean

Oh, geezzzzz. Wrong link. I meant http://portal.acm.org/citation.cfm?id=967471 . Louis Wasserman wasserman.louis@gmail.com On Tue, Sep 8, 2009 at 1:06 PM, Louis Wasserman wrote:

Sean,

The answer is, I'm working on a recently semi-released package called TrieMap.

The objective of this package, building off of the work in this paperhttps://docs.google.com/Doc?docid=0AWuaUF8ZNTNDZHB3emdyaF8zMzNmZmtmcHo2Yw&hl=en, is to automatically derive the type of a generalized trie for any algebraic type based on its algebraic representation. (I am working on writing up my methods for publication.)

Of course, if I could get automatic access to the mechanisms of a type's constructors, I wouldn't even require users to describe the algebraic representation of their type...

Louis Wasserman wasserman.louis@gmail.com

On Tue, Sep 8, 2009 at 2:34 AM, Sean Leather wrote:

...

...

I don't know a thing about SYB, Data.Data, or Data.Typeable, mostly because I'm an efficiency fanatic. Nevertheless, I'd like to know whether or not there's a way to deconstruct a (mostly) arbitrary type, into tuples, unions, etc. using this framework. Any thoughts?

You can use the Template Haskell deriving in EMGM to get that structure pretty efficiently.

http://www.cs.uu.nl/wiki/GenericProgramming/EMGM http://hackage.haskell.org/package/emgm

The obligatory question is: why do you want it?

Sean

The goal is similar, but I'm attempting to automatically infer the appropriate map type for any algebraic datatype -- and while I'm at it, the TrieMap package aims to include all the methods Data.Map offers. Louis Wasserman wasserman.louis@gmail.com 2009/9/9 José Pedro Magalhães

Hello Louis,

On Tue, Sep 8, 2009 at 19:06, Louis Wasserman wrote:

...

Sean,

The answer is, I'm working on a recently semi-released package called TrieMap.

Is that similar to what is done in [1]? A draft paper [2] also refers that implementation.

Cheers, Pedro

[1] http://www.haskell.org/haskellwiki/GHC/Indexed_types#An_associated_data_type... [2] http://www.cse.unsw.edu.au/~chak/project/generics/

This is about the same as the other paper I linked to, I think, but I'm interested in actually connecting the fully general trie construction to Template Haskell and other facilities to reduce the coder's overhead of using these tries in practice to a minimum. Louis Wasserman wasserman.louis@gmail.com On Wed, Sep 9, 2009 at 10:24 AM, Sean Leather wrote:

The goal is similar, but I'm attempting to automatically infer the

...

appropriate map type for any algebraic datatype -- and while I'm at it, the TrieMap package aims to include all the methods Data.Map offers.

Perhaps you want to read about the type-indexed tries in "Generic Haskell: Applications": http://www.cs.uu.nl/~johanj/publications/ghpractice.pdf

Sean