55 ms·

This post is specially relevant for me, since last weekend I've decided to take a quick look at Clojure, as one of my personal goals this year is to get acquain

This post is specially relevant for me, since last weekend I've decided to take a quick look at Clojure, as one of my personal goals this year is to get acquainted with a Lisp dialect. From my _very_ short experience (I've started coding a simple game), here are my two cents: - If your application is heavily dependent on state, which changes continuously and must be maintained during most of the execution time - like a game - it may not be a good fit. You'll waste a lot of working around the fact that each modification results on new objects. - If your application comprises mainly of short requests that may create some state that will most certainly be discarded shortly after - like a web application - then I think it's a good fit and you'll probably enjoy it better. Once again, I've just got started with it, so take this with a grain of salt :)

tesmar2 14y ago
Thanks for this. I'd hate to start down the road of writing a game in clojure.... I may try the blog/webapp idea with Clojure.
- jrheard 14y ago
  Programming a game in Clojure might not be such a bad idea - mikera has some really great thoughts at http://stackoverflow.com/questions/9755882/are-functional-programming-languages-suitable-for-graphics-programming http://stackoverflow.com/questions/9755882/are-functional-pr... . Also, you might find this series of blog posts interesting: http://briancarper.net/blog/520/making-an-rpg-in-clojure-part-one-of-many http://briancarper.net/blog/520/making-an-rpg-in-clojure-par...
  - EastCoastLA 14y ago
    Don't forget: The Caves of Clojure - steve losh http://stevelosh.com/blog/2012/07/caves-of-clojure-01/ http://stevelosh.com/blog/2012/07/caves-of-clojure-01/
aphyr 14y ago
I'd like to contrast this: if your application is heavily dependent on state, especially state which is shared between threads, Clojure offers a concise, safe, and uniform way to understand and organize state transformations--at the cost of performance. Where fast mutability is required, it's easy to drop down to explicit locks, atomics, java.util.concurrent collections, et al. I find the majority of my time in writing stateful programs goes towards reasoning about safety, and having access to STM lets me write correct code with less thinking. Then I focus on optimizing the parts where performance is critical.
- billsix 14y ago
  At ILC 2009, Guy Steele asked Rich Hickey how Clojure's STM interacted with I/O. To which, Rich replied that it doesn't. No further discussion continued on the subject. I have found that this rarely enters discussions regarding Clojure, although the STM is frequently lauded. GHC's STM also does not work with the IOMonad, which is clear because of the types, and is articulated in books such as such as Real World Haskell. http://book.realworldhaskell.org/read/software-transactional-memory.html http://book.realworldhaskell.org/read/software-transactional... Are people really getting benefits from transactions which do not involve I/O?
  - jrheard 14y ago
    That's odd, that seems a little inaccurate to me. Clojure's agents are useful for encapsulating I/O-related resources, and are integrated with the STM system. Per http://clojure.org/agents http://clojure.org/agents - Agents are integrated with the STM - any dispatches made in a transaction are held until it commits, and are discarded if it is retried or aborted.
    - craigching 14y ago
      I'm a clojure newb myself, but I thought STM transactions weren't allowed to have side-effects and IO would be a side-effect, no?
      - 14y ago
julsonl 14y ago
For games, Chris Granger and his team have coded up a prototype game in Clojurescript using the Entity-Component-System architecture, which seems to be a good fit for functional languages. It might be worth checking out: http://www.chris-granger.com/2012/12/11/anatomy-of-a-knockout/ http://www.chris-granger.com/2012/12/11/anatomy-of-a-knockou...
Tuna-Fish 14y ago
Actually, in my experience the practises in the high-end AAA game industry are now much closer to FP than the rest of the industry. The current-gen consoles have lots of really weak threads, and to get any decent performance you have to use a lot of them. So, modern games do things like double-buffer the entire world state to allow efficient multithreading. Of course, everyone there is doing FP in C++.

tesmar2 14y ago

Thanks for this. I'd hate to start down the road of writing a game in clojure.... I may try the blog/webapp idea with Clojure.

jrheard 14y ago
Programming a game in Clojure might not be such a bad idea - mikera has some really great thoughts at http://stackoverflow.com/questions/9755882/are-functional-programming-languages-suitable-for-graphics-programming http://stackoverflow.com/questions/9755882/are-functional-pr... . Also, you might find this series of blog posts interesting: http://briancarper.net/blog/520/making-an-rpg-in-clojure-part-one-of-many http://briancarper.net/blog/520/making-an-rpg-in-clojure-par...
- EastCoastLA 14y ago
  Don't forget: The Caves of Clojure - steve losh http://stevelosh.com/blog/2012/07/caves-of-clojure-01/ http://stevelosh.com/blog/2012/07/caves-of-clojure-01/

aphyr 14y ago

I'd like to contrast this: if your application is heavily dependent on state, especially state which is shared between threads, Clojure offers a concise, safe, and uniform way to understand and organize state transformations--at the cost of performance. Where fast mutability is required, it's easy to drop down to explicit locks, atomics, java.util.concurrent collections, et al. I find the majority of my time in writing stateful programs goes towards reasoning about safety, and having access to STM lets me write correct code with less thinking. Then I focus on optimizing the parts where performance is critical.

billsix 14y ago
At ILC 2009, Guy Steele asked Rich Hickey how Clojure's STM interacted with I/O. To which, Rich replied that it doesn't. No further discussion continued on the subject. I have found that this rarely enters discussions regarding Clojure, although the STM is frequently lauded. GHC's STM also does not work with the IOMonad, which is clear because of the types, and is articulated in books such as such as Real World Haskell. http://book.realworldhaskell.org/read/software-transactional-memory.html http://book.realworldhaskell.org/read/software-transactional... Are people really getting benefits from transactions which do not involve I/O?
- jrheard 14y ago
  That's odd, that seems a little inaccurate to me. Clojure's agents are useful for encapsulating I/O-related resources, and are integrated with the STM system. Per http://clojure.org/agents http://clojure.org/agents - Agents are integrated with the STM - any dispatches made in a transaction are held until it commits, and are discarded if it is retried or aborted.
  - craigching 14y ago
    I'm a clojure newb myself, but I thought STM transactions weren't allowed to have side-effects and IO would be a side-effect, no?
    - 14y ago

julsonl 14y ago

For games, Chris Granger and his team have coded up a prototype game in Clojurescript using the Entity-Component-System architecture, which seems to be a good fit for functional languages. It might be worth checking out: http://www.chris-granger.com/2012/12/11/anatomy-of-a-knockout/ http://www.chris-granger.com/2012/12/11/anatomy-of-a-knockou...

Tuna-Fish 14y ago

Actually, in my experience the practises in the high-end AAA game industry are now much closer to FP than the rest of the industry. The current-gen consoles have lots of really weak threads, and to get any decent performance you have to use a lot of them. So, modern games do things like double-buffer the entire world state to allow efficient multithreading. Of course, everyone there is doing FP in C++.