I once set out to make a ticket for it, but ended up not probably because it was going to take too much effort to describe or something. I was probably busy.
On Saturday, October 24, 2015 at 7:01:05 PM UTC-5, Gary Fredericks wrote: > > I've always thought this is bad behavior, since it's blatantly doing the > opposite of what the name advertises. I think either the boxed versions > should return the same result as the unboxed version, or (if the whole > point is to give good performance and so we don't want want users to be > able to accidentally use the unboxed versions) it should throw at > compile-time for boxed args. > > On Saturday, October 24, 2015 at 9:35:46 AM UTC-5, Andy Fingerhut wrote: >> >> I can't answer whether Clojure should do that. >> >> It is doing it because unchecked-multiply falls back to normal multiply, >> i.e. *, unless both of its arguments are primitive long values. Even boxed >> Long values cause it to fall back to the behavior of *. The same goes for >> unchecked-add and unchecked-subtract. >> >> >> user=> (unchecked-multiply 2432902008176640000 21) >> -4249290049419214848 >> user=> (unchecked-multiply 2432902008176640000 (Long. 21)) >> >> ArithmeticException integer overflow >> clojure.lang.Numbers.throwIntOverflow (Numbers.java:1501) >> >> Andy >> >> >> On Fri, Oct 23, 2015 at 1:54 PM, Garrett Rowe <gmrow...@gmail.com> wrote: >> >>> Should `unchecked-multiply` throw an exception in this case? (see also: >>> http://stackoverflow.com/questions/33306984/why-does-my-hash-function-fail-with-arithmeticexception-integer-overflow-even/33308956#33308956 >>> ) >>> >>> user> (reduce unchecked-multiply (range 1 22)) >>> ArithmeticException integer overflow clojure.lang.Numbers.throwIntOverflow >>> (Numbers.java:1388) >>> >>> The loop-recur version also fails, unless you use a type hint: >>> >>> user> (loop [n 1 >>> r (range 1 22)] >>> (if-let [a (first r)] >>> (recur (unchecked-multiply n a) (next r)) >>> n)) >>> ArithmeticException integer overflow clojure.lang.Numbers.throwIntOverflow >>> (Numbers.java:1388) >>> >>> user> (loop [n 1 >>> r (range 1 22)] >>> (if-let [^long a (first r)] >>> (recur (unchecked-multiply n a) (next r)) >>> n)) >>> -4249290049419214848 >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Clojure" group. >>> To post to this group, send email to clo...@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+u...@googlegroups.com >>> For more options, visit this group at >>> http://groups.google.com/group/clojure?hl=en >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "Clojure" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to clojure+u...@googlegroups.com. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- 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 --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
