Hi Mark, I think the def inside a defn has to go, it looks like an accident in waiting. I think you are replacing globals with a "god" structure (game) which passed to every function, I think you need to abstract more. I'm afraid I don't like the "big let" style and I found it hard to follow some of your code, that may just be a personal thing but a lot of the vars defined in let are only used once and could be inlined.
I do like the state loop approach but I don't see why you need that global. Cheers Tom 2009/1/7 Mark Volkmann <r.mark.volkm...@gmail.com> > > On Tue, Jan 6, 2009 at 3:07 PM, Mark Engelberg <mark.engelb...@gmail.com> > wrote: > > > > One way to approach this without mutation is as follows: > > > > Decide on a data representation that represents the entire state of > > the game world at a given instant. > > > > Write a function which can draw this state. > > Write a function which takes the state and player keypresses as input, > > and returns a new updated state. > > Write a function which takes the state and returns the new state just > > from time elapsing. > > > > Note that none of the above functions mutate anything. It's all about > > returning fresh states, which fits well with Clojure's standard > > handling of data structures. > > > > Then write a loop that consumes an initial state, and creates a game > > experience by repeatedly applying the above functions. No globals or > > refs are required, just keep passing the new states back into the loop > > for further processing. > > > > This is an outline of the strategy employed by the "world" teachpack > > that accompanies the "How to Design Programs" curriculum that uses PLT > > Scheme. Students routinely develop the snake program as a homework > > assignment, using this approach. > > Excellent suggestions! I spent many hours today rewriting my snake > program to do this. The new version is at > http://www.ociweb.com/mark/programming/ClojureSnake.html. It doesn't > use any refs or transactions. Parts of it are greatly simplified over > what I had before. For example, creation of the JPanel proxy is > shorter. > > I only have one global remaining and can't figure out how to get rid > of it. It is the key code of the last key pressed. That gets set in > the keyPressed method of the JPanel which is a KeyListener. > > I know we're beating this into the ground, but feedback is still > welcomed. If you see anything in the code that you would do > differently, I'd be interested in hearing about it. > > -- > R. Mark Volkmann > Object Computing, Inc. > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -~----------~----~----~----~------~----~------~--~---
