On Thu, Mar 31, 2016 at 10:36:45AM -0700, Lucas Sloan wrote: > I have some mutually recursive code as follows: > > (ns tester.core > (:require [clojure.data.json :as json]) > (:gen-class)) > > (defn getValuePathPairs > [json] > (cond > (instance? clojure.lang.PersistentVector json) (getVectorValuePathPairs > json) > (instance? clojure.lang.PersistentArrayMap json) (getMapValuePathPairs > json) > (instance? Boolean json) [[json ""]] > (instance? Number json) [[json ""]] > (instance? String json) [[json ""]]) > ) > > (defn getVectorValuePathPairs > [vec] > (mapcat (fn [[i e]] > (for [[leaf-value path] (getValuePathPairs e)] > [leaf-value (str "[" i "]" path)])) > (map-indexed vector vec)) > ) > > > (defn getMapValuePathPairs > [m] > (mapcat (fn [[k v]] > (for [[leaf-value path] (getValuePathPairs v)] > [leaf-value (str "[" k "]" path)])) > m) > ) > > (defn -main > "I don't do a whole lot ... yet." > [& args] > (println (getValuePathPairs ["Blah" 1 true]))) > > getValuePathPairs calls getVectorValuePathPairs and getMapValuePathPairs, > which in turn call getValuePathPairs. When I try to compile and run this > code I get the following error: > > Exception in thread "main" java.lang.RuntimeException: Unable to resolve > symbol: getVectorValuePathPairs in this context, > compiling:(tester/core.clj:8:52) > > > It appears from my experimentation that the issue is that when compiling > getValuePathPairs, > the function getVectorValuePathPairs isn't yet defined, as when I compile > this into a CIDER repl with the recursion taken out, then compiled again > with it put back it runs just fine. > > > Googling about mutual recursion in clojure provides a lot of hits about > lack of tail call optimization, but no one saying that it's impossible to > do (given short recursive depths). In this particular piece of code, I > could just inline the two inner functions, but I'd be giving up a lot of > readability. Is there a way to compile mutually recursive code? If not, > is there a good way to structure this sort of code so I can pull out small > functions and name them without running into this problem?
Why not forward declare the required functions with (declare ...)? -- 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.
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