Re: simple debugging utility
On Mar 24, 2009, at 15:44, Mark Volkmann wrote: I'm wondering if there is a way to avoid that using a macro. The hard part is printing the expression. The following doesn't work. It outputs 3 = 3. (defmacro dump2 [expr] `(let [value# ~expr] (pr ~expr) (println = value#))) (dump2 (+ 1 2)) All it takes to make it work is a slight modification: (defmacro dump [expr] `(let [value# ~expr] (pr (quote ~expr)) (println = value#))) (dump (+ 1 2)) prints: (+ 1 2) = 3 Konrad. --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Re: simple debugging utility
On Tue, Mar 24, 2009 at 9:55 AM, Konrad Hinsen konrad.hin...@laposte.net wrote: On Mar 24, 2009, at 15:44, Mark Volkmann wrote: I'm wondering if there is a way to avoid that using a macro. The hard part is printing the expression. The following doesn't work. It outputs 3 = 3. (defmacro dump2 [expr] `(let [value# ~expr] (pr ~expr) (println = value#))) (dump2 (+ 1 2)) All it takes to make it work is a slight modification: (defmacro dump [expr] `(let [value# ~expr] (pr (quote ~expr)) (println = value#))) (dump (+ 1 2)) prints: (+ 1 2) = 3 Thanks! It looks like I don't need the let now. Does a macro have to evaluate to one form? For example, this works, but it seems I can't drop the do. (defmacro dump [expr] `(do (print (quote ~expr)) (println = ~expr))) -- R. Mark Volkmann Object Computing, Inc. --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Re: simple debugging utility
2009/3/24 Mark Volkmann r.mark.volkm...@gmail.com: Thanks! It looks like I don't need the let now. Does a macro have to evaluate to one form? For example, this works, but it seems I can't drop the do. (defmacro dump [expr] `(do (print (quote ~expr)) (println = ~expr))) How about: (defmacro dump [expr] `(println '~expr = ~expr)) R. Mark Volkmann -- ! Lauri --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Re: simple debugging utility
On Mar 24, 2009, at 16:00, Mark Volkmann wrote: Thanks! It looks like I don't need the let now. Indeed. Does a macro have to evaluate to one form? For example, this works, but it seems I can't drop the do. Yes, a macro has to evaluate to one form. This is actually not so much a condition on macros as a consequence of the fact that a macro, like any function, has a single return value. What else could that reasonably be but a form? Konrad. --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Re: simple debugging utility
Eric Rochester has a debug macro, together with a walkthrough of how he built it, here http://writingcoding.blogspot.com/2008/09/stemming-part-19-debugging.html Joshua On Tue, Mar 24, 2009 at 4:43 PM, Mark Volkmann r.mark.volkm...@gmail.comwrote: I want to write a function or macro that allows me to output the value of an expression without repeating it. For example, I want something like (dump (+ 1 2)) to output (+ 1 2) = 3. This works. (defn dump1 [string] (println string = (load-string string))) (dump1 (+ 1 2)) Note how I had to put the expression passed to dump1 in quotes to make a string. I'm wondering if there is a way to avoid that using a macro. The hard part is printing the expression. The following doesn't work. It outputs 3 = 3. (defmacro dump2 [expr] `(let [value# ~expr] (pr ~expr) (println = value#))) (dump2 (+ 1 2)) -- R. Mark Volkmann Object Computing, Inc. --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Re: simple debugging utility
For reference, here's a version I wrote while I was working on cl- format and the pretty printer: (defn prerr [ args] Println to *err* (binding [*out* *err*] (apply println args))) (defmacro prlabel [prefix arg more-args] Print args to *err* in name = value format (cons 'prerr (cons (list 'quote prefix) (mapcat #(list (list 'quote %) = %) (cons arg more- args) It prints a label (which is a string, but the macro quotes it for you and a set of forms you want to print. Using the above example, this would be (prlabel foo (+ 1 2)) and it would print: foo (+ 1 2) = 3 A real example from the PrettyWriter is: (prlabel tf? (.getColumn this) (buffer-length tokens)) I make sure the output goes to *err* partially because that just seems right for trace output and partially because cl-format tends to have *out* bound at its whim. Tom On Mar 24, 8:32 am, Joshua Fox joshuat...@gmail.com wrote: Eric Rochester has a debug macro, together with a walkthrough of how he built it, herehttp://writingcoding.blogspot.com/2008/09/stemming-part-19-debugging Joshua On Tue, Mar 24, 2009 at 4:43 PM, Mark Volkmann r.mark.volkm...@gmail.comwrote: I want to write a function or macro that allows me to output the value of an expression without repeating it. For example, I want something like (dump (+ 1 2)) to output (+ 1 2) = 3. This works. (defn dump1 [string] (println string = (load-string string))) (dump1 (+ 1 2)) Note how I had to put the expression passed to dump1 in quotes to make a string. I'm wondering if there is a way to avoid that using a macro. The hard part is printing the expression. The following doesn't work. It outputs 3 = 3. (defmacro dump2 [expr] `(let [value# ~expr] (pr ~expr) (println = value#))) (dump2 (+ 1 2)) -- R. Mark Volkmann Object Computing, Inc. --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Re: simple debugging utility
Hi, Am 24.03.2009 um 16:00 schrieb Mark Volkmann: Thanks! It looks like I don't need the let now. But there are reasons to keep it! Eg. returning the expression result! (defmacro dump [expr] `(let [value# ~expr] (println (pr-str (quote ~expr)) = (pr-str value#)) value#)) Then you can mix in your dump macro where you want. Your version always returns nil. Or you can have a look at clojure.contrib.trace. Sincerely Meikel smime.p7s Description: S/MIME cryptographic signature
