はてなブックマーク

May 23, 2010 [Clojure concurrency - part 3] A Clojure `Ref' is the solution to the problem discussed in the last post. Here is how you create a `ref': (def p (ref 0)) The value of a ref can be changed by `ref-set': (ref-set p 1) But this doesn't work! We get an exception. The idea is that the ref can be changed only from within a `transaction': (dosync (ref-set p 1)) What is so special about a `tr