Re: [Haskell-cafe] Functional GUI combinators for arbitrary graphs ofcomponents?
Paul Hudak wrote: Brian Hulley wrote: Anyway to get to my point, though all this sounds great, I'm wondering how to construct an arbitrary graph of Fudgets just from a fixed set of combinators, such that each Fudget (node in the graph) is only mentioned once in the expression. To simplify the question, If you consider just Dags, I believe that this question is equivalent to asking what set of combinators will allow you to create an arbitrary composition of functions that allow sharing inputs and returning multiple results. And I think that one answer to that is the set of combinators that make up the Arrow class. If you want to include recursion (i.e. cycles), then you'd have to throw in ArrowLoop (although that might only provide a nested form of cycles). It's in this sense that Fudgets is analogous to Fruit. Thanks. Actually thinking more about it I've probably missed the point that for a compositional GUI there's no need for a general graph, since each view/controller of the underlying model could be encapsulated as a single widget (eg fudget or signal transformer) which could be connected to the model via a loop which exposes only the model (thus allowing other views to be added later). Brian. -- http://www.metamilk.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Functional GUI combinators for arbitrary graphs ofcomponents?
If you consider just Dags, I believe that this question is equivalent to asking what set of combinators will allow you to create an arbitrary composition of functions that allow sharing inputs and returning multiple results. And I think that one answer to that is the set of combinators that make up the Arrow class. If you want to include recursion (i.e. cycles), then you'd have to throw in ArrowLoop (although that might only provide a nested form of cycles). It's in this sense that Fudgets is analogous to Fruit. -Paul Brian Hulley wrote: Brian Hulley wrote: Anyway to get to my point, though all this sounds great, I'm wondering how to construct an arbitrary graph of Fudgets just from a fixed set of combinators, such that each Fudget (node in the graph) is only mentioned once in the expression. To simplify the question, assume we have the following data structure to describe the desired graph: data LinkDesc a = Series a a | Broadcast a [a] | Merge [a] a type GraphDesc a = [LinkDesc a] The above is more complicated than necessary. The problem can be captured by: type GraphDesc a = [(a,a)] Brian. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Functional GUI combinators for arbitrary graphs ofcomponents?
Brian Hulley wrote: Anyway to get to my point, though all this sounds great, I'm wondering how to construct an arbitrary graph of Fudgets just from a fixed set of combinators, such that each Fudget (node in the graph) is only mentioned once in the expression. To simplify the question, assume we have the following data structure to describe the desired graph: data LinkDesc a = Series a a | Broadcast a [a] | Merge [a] a type GraphDesc a = [LinkDesc a] The above is more complicated than necessary. The problem can be captured by: type GraphDesc a = [(a,a)] Brian. -- http://www.metamilk.com ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
