Wow, forget everything I said, this has nothing to do with macro expansion. Looks more like inside a function you can only def something in the same namespace as the function:
user> (defn ff [] (in-ns 'foo.core2) (def anything5 10)) #'user/ff user> anything5 Var user/anything5 is unbound. [Thrown class java.lang.IllegalStateException] user> (ff) #'user/anything5 foo.core2> (in-ns 'foo.core2) #<Namespace foo.core2> foo.core2> (def anything6 10) #'foo.core2/anything6 On Mon, Aug 15, 2011 at 9:36 PM, Mark Rathwell <mark.rathw...@gmail.com> wrote: > You are correct, I must have messed something up in my expansions. > From the below, however, it looks like a var is being declared just by > having the macro called, but not bound to the value: > > user> (defmacro foo [name & body] `(def ~name ~(identity `(fn [] ~@body)))) > #'user/foo > user> (foo xx (in-ns 'foo.core) (def anything3 10)) > #'user/xx > user> anything3 > > Var user/anything3 is unbound. > [Thrown class java.lang.IllegalStateException] > > user> anything4 > > Unable to resolve symbol: anything4 in this context > [Thrown class java.lang.Exception] > > > On Mon, Aug 15, 2011 at 8:56 PM, Alan Malloy <a...@malloys.org> wrote: >> I either disagree or don't understand. The deftest macro doesn't touch >> your &body arg; it's expanded as-is. For example, (let [x 'foo] `(inc >> ~x)) doesn't result in foo getting qualified, and most macros behave >> the same way. >> >> On Aug 15, 4:36 pm, Mark Rathwell <mark.rathw...@gmail.com> wrote: >>> Just to be clear, it is namespace resolved because of syntax quote: >>> >>> (defmacro deftest >>> [name & body] >>> (when *load-tests* >>> `(def ~(vary-meta name assoc :test `(fn [] ~@body)) >>> (fn [] (test-var (var ~name)))))) >>> >>> >>> >>> >>> >>> >>> >>> On Mon, Aug 15, 2011 at 7:23 PM, Alan Malloy <a...@malloys.org> wrote: >>> > Is it? That's neat; I guess I've never thought about how the compiler >>> > treats def. Thanks for the explanation. >>> >>> > On Aug 15, 3:03 pm, Mark Rathwell <mark.rathw...@gmail.com> wrote: >>> >> deftest is a macro. Macros are expanded at compile time. So, in this >>> >> case, at compile time, a function called namespace2 is def'd with meta >>> >> data :test set to the body of your deftest. >>> >>> >> All of that body is namespace resolved in macro expansion, before >>> >> in-ns is ever executed (which happens when you actually call the >>> >> namespace2 function created by the macro). Put another way, (def >>> >> anything 10) is namespace resolved to (def >>> >> learn.clojure.test.core/anything 10) at macro expansion time (compile >>> >> time), before the test function is ever called, and thereby before >>> >> in-ns is ever executed. >>> >>> >> Hope this helps. >>> >> On Mon, Aug 15, 2011 at 5:07 PM, Richard Rattigan <ratti...@gmail.com> >>> >> wrote: >>> >>> >> > I'm finding that namespaces don't seem to behave as I expect >>> >> > intuitively, or according to the reference. It's quite possible I'm in >>> >> > the wrong here though, as I'm just kicking clojure's tires at this >>> >> > point. >>> >>> >> > Here is the relevant doc: >>> >>> >> >http://clojure.org/special_forms >>> >> > (def symbol init?) >>> >> > Creates and interns or locates a global var with the name of symbol >>> >> > and a namespace of the value of the current namespace (*ns*). >>> >>> >> > In the test below, which succeeds, the var does not appear to end up >>> >> > in the "current namespace" per this definition. Am I misinterpreting >>> >> > something, or is this a deviation from the spec/reference? >>> >>> >> > (ns learn.clojure.test.core >>> >> > (:use [clojure.test])) >>> >> > (deftest namespace2 >>> >> > (in-ns 'my.new.namespace) >>> >> > ;confirm the current namespace >>> >> > (is (= "my.new.namespace" (str *ns*))) >>> >> > ;attempt to def a var in the current namespace >>> >> > (def anything 10) >>> >> > ;the var is not defined in the current namespace >>> >> > (is (nil? (ns-resolve *ns* 'anything))) >>> >> > ;the var is however definined in the orginal namespace >>> >> > (is (not (nil? (ns-resolve (find-ns 'learn.clojure.test.core) >>> >> > 'anything)))) >>> >> > (is (= 10 learn.clojure.test.core/anything))) >>> >>> > -- >>> > 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 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. 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