Thanks, Eric. My original problem was the factorial function, which breaks despite using BigInts:
user=> (defn fact [n] (if (<= n 1N) 1N (* n (fact (- n 1N))))) #'user/fact user=> (type (fact 1)) clojure.lang.BigInt user=> (type (fact 20)) java.lang.Long user=> (type (fact 21)) ArithmeticException integer overflow clojure.lang.Numbers.throwIntOverflow (Num bers.java:1374) The optimization to using Longs seems to be too aggressive. Upgrade casting in Clojure 1.2 is cool and simple. Dominikus On Sep 8, 1:30 pm, Eric Lavigne <lavigne.e...@gmail.com> wrote: > You have discovered a very recent change. The idea is to automatically > switch to longs for performance when it is clear that overflow will > not occur. > > https://github.com/clojure/clojure/commit/684fca15040e1ec8753429909b2... > > There are still some problems with this optimization, which will > hopefully be worked out before the final 1.3 release. > > http://dev.clojure.org/jira/browse/CLJ-836 > > > > > > > > On Thu, Sep 8, 2011 at 6:25 AM, Dominikus <dominikus.herzb...@gmail.com> > wrote: > > In Clojure 1.3, BigInts are said to be "contagious" across operations. > > > """ > > When different types of numbers are used in a math operation, the > > result will be the larger or more general of the two types. For > > example, any integer operation involving a BigInt will result in a > > BigInt, [...]. > > """ > >http://dev.clojure.org/display/doc/Documentation+for+1.3+Numerics > > > However (type (- 2 1N)) results in java.lang.Long and does not seem to > > work accordingly. What's going on here? -- 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 Note that posts from new members are moderated - please be patient with your first post. 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
