The compiler uses recursive descent in its analysis. Given a VM call stack that does not grow, there will always been some input that causes the compiler to blow stack. In the case of cond, the macro expands into a nested if statements. Given enough clauses, you get the result you have experienced.
There are several solutions. (1) Rewrite the compiler to make the analysis use an explicite (heap-allocated) stack. That would be a lot of work. It's not going on my short list anytime soon. (2) Rewrite the compiler to run on a separate thread and create a way (a command-line option, for example) to configure the stack size on the compiler thread. (3) Recompile (actually re-link) Clojure.Main.exe to have a larger stack size. See http://msdn.microsoft.com/en-us/library/8cxs58a6(v=vs.100).aspx (4) Edit the Clojure.Main.exe executable to have a larger stack size. The EDITBIN.EXE program is often used for this. See http://msdn.microsoft.com/en-us/library/xd3shwhf(v=vs.110).aspx. (5) Break up your cond into several (non-nested) statements. Solutions (1) through (4) require access to the CLR compiler toolset or Visual Studio. -David On Saturday, November 17, 2012 10:37:38 AM UTC-6, FC wrote: > > When ClojureCLR (.NET 3.5 build) evals a cond form with 1024 clauses it > throws a StackOverflowException. > > Cond example code in pastebin: http://pastebin.com/K4QQmjNF > Save the example code to bigcond.clj and run Clojure.Main like: > Clojure.Main bigcond.clj > > The number of cond clauses needed to cause a stack overflow varies. > > Stack trace: > > System.StackOverflowException was unhandled > > > > Clojure.dll!clojure.lang.ASeq.ASeq(clojure.lang.IPersistentMap meta) > Line 44 + 0xa bytes C# > > Clojure.dll!clojure.lang.TypedArraySeq<object>.TypedArraySeq(clojure.lang.IPersistentMap > > meta, object[] array, int index) Line 241 + 0xf bytes C# > > Clojure.dll!clojure.lang.ArraySeq_object.ArraySeq_object(clojure.lang.IPersistentMap > > meta, object[] array, int index) Line 734 + 0x19 bytes C# > Clojure.dll!clojure.lang.ArraySeq.create(object[] array) Line 41 + 0x44 > bytes C# > > -- 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
