why is there an exception for Boolean.FALSE? Am 07.04.2012 17:28, schrieb Softaddicts: > Hi, > > You are not in the Clojure play ground when you use (Boolean. false). > > This expression creates a Java object, hence (if any-java-object ...) > always evaluate the "true" branch in Clojure. > > In Clojure, anything not nil is true except false which is equivalent to the > Java > false value. > (if false....) (if nil ...) will both evaluate the "false" branch. > > In your specific case, (if (.booleanValue (Boolean. false)) ...) would > correctly > evaluate since booleanValue returns the value in the object, not the > object itself. > > If you can, stay in Clojure and avoid Java for a while until you get more > code lines behind you. > > Hope I am clear enough, just woke up :) > > Luc > > >> Hi, >> >> I am using Clojure for a month now. I like it a lot so far, but there >> are a couple of little details that make me very afraid. Foremost: >> >> (if (Boolean. false) "jesus" "christ") >> >> will return "jesus", not "christ". Googling this on the net, I found >> that this is a known phenomenon, and some rationalizations of why this >> is the correct thing to do (it is not, sorry Rich). >> >> I could live with this, but I have code that is written completely in >> clojure, and does not create Boolean objects in any explicit way, or >> uses third-party libraries except for the stuff in clojure.core and >> slingshot. Nevertheless, somehow Boolean objects seem to creep into >> live, and I have code like that: >> >> (if (:leaf m-node) >> .... >> ... >> ) >> >> that breaks because of it. I am using from the github repository >> ( 14428c296de483ea666bd874701046e7088e545c). >> >> This means that I cannot trust my code on the most basic level, and >> this is unacceptable. >> >> >> -- >> 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 >> > -- > Softaddicts<lprefonta...@softaddicts.ca> sent by ibisMail! >
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