You are not defining a type here. A type hint is just that... a hint so the compiler can optimize the code it generates to call the readLine method on this specific object class.
As an example, if io/reader returned an object of a different class at runtime than BufferedReader, it would not fail even if the hint says "expect an object of this class". The generated code testing that the object is not of the hinted class would resort to reflection on the object class to find if the readLine method exists. If not you will get the usual runtime error saying that the method does not exists. The Clojure compiler has no type checking equivalent to Java, C, ... You can define stuff that is not even bound to a value, it would be hard to type check on these at compile time, no ? Welcome to a world of values, not containers (the blue pieces can only fit in the blue container, the red ones .... you get the picture) or as Rich says places. Luc P. > That's funny, I did exactly the same thing and wrote BufferedReader for > both. DOH! > > Although I have no idea how the internals of type hinting is, I do think > it's peculiar that there doesn't seem to be type error checking, even > though we are explicitly "defining" the type. I would feel like it should > error, instead of falling back on reflection. > > Kanwei > > On Monday, February 4, 2013 12:36:51 PM UTC-5, AtKaaZ wrote: > > > > in other words: > > this: > > > > (let [in (clojure.java.io/reader src) > > out (clojure.java.io/writer dest) > > > > > > becomes this: > > (let [^java.io.BufferedReader in (clojure.java.io/reader src) > > ^java.io.BufferedWriter out (clojure.java.io/writer dest) > > > > > > and it works for me too. (but I wasted some time by having BufferedReader > > in both places) > > > > > > On Mon, Feb 4, 2013 at 6:26 PM, Andy Fingerhut > > <andy.fi...@gmail.com<javascript:> > > > wrote: > > > >> I don't have CCW Eclipse installed to test, but by saving that file on my > >> Mac (should also work on Linux) in a subdirectory "obj", and editing it to > >> add the ^java.io.BufferedReader in and ^java.io.BufferedWriter out type > >> hints as suggested by Luc P. earlier in this thread, I was able to > >> eliminate the reflection warnings: > >> > >> % mkdir obj > >> % cp <gist_file> obj/solutions.clj > >> > >> # Original file without the type hints gives reflection warnings as > >> expected > >> > >> % java -Dclojure.compile.path=./obj -cp clojure-1.4.0.jar:./obj > >> clojure.lang.Compile solution > >> Compiling solution to ./obj > >> Reflection warning, solution.clj:38 - reference to field readLine can't > >> be resolved. > >> Reflection warning, solution.clj:45 - reference to field readLine can't > >> be resolved. > >> Reflection warning, solution.clj:63 - reference to field newLine can't be > >> resolved. > >> Reflection warning, solution.clj:54 - reference to field newLine can't be > >> resolved. > >> > >> # Now I hand-edit obj/solutions.clj to add the type hints, and recompile. > >> No reflection warnings. > >> % java -Dclojure.compile.path=./obj -cp clojure-1.4.0.jar:./obj > >> clojure.lang.Compile solution > >> Compiling solution to ./obj > >> % > >> > >> Perhaps you should try verifying that you added the type hints correctly, > >> saved the source file, recompiled the one you wanted to in CCW Eclipse, > >> etc. > >> > >> Andy > >> > >> > >> On Feb 4, 2013, at 9:10 AM, Kanwei Li wrote: > >> > >> Hey Andy, > >> > >> Thanks for offering to help. Here's a gist: > >> https://gist.github.com/4696105 > >> > >> As you can see at the bottom, I want the main method to read/write to > >> STDIN/STDOUT, but for testing, I want to read from files instead. > >> > >> This is what I get in both CCW Eclipse and nrepl: > >> > >> Reflection warning, NO_SOURCE_PATH:4 - reference to field readLine can't > >> be resolved. > >> > >> Reflection warning, NO_SOURCE_PATH:11 - reference to field readLine can't > >> be resolved. > >> > >> Reflection warning, NO_SOURCE_PATH:29 - reference to field newLine can't > >> be resolved. > >> > >> Reflection warning, NO_SOURCE_PATH:20 - reference to field newLine can't > >> be resolved. > >> Thanks! > >> > >> On Sunday, February 3, 2013 4:38:38 PM UTC-5, Andy Fingerhut wrote: > >>> > >>> Can you post a larger chunk of code for us to examine, perhaps on github > >>> or as a gist if it is over 30 lines of code or so? Many of us have had > >>> good success with eliminating reflection using type hints, so it should > >>> be > >>> possible to make it work. > >>> > >>> Andy > >>> > >>> On Feb 3, 2013, at 12:50 PM, Kanwei Li wrote: > >>> > >>> Unfortunately it doesn't work. > >>> > >>> Reflection warning, NO_SOURCE_PATH:20 - call to write can't be resolved. > >>> > >>> Reflection warning, NO_SOURCE_PATH:21 - reference to field newLine can't > >>> be resolved. > >>> > >>> On Sunday, February 3, 2013 2:35:23 PM UTC-5, Luc wrote: > >>>> > >>>> Why not add type hints like this ? > >>>> > >>>> (let [^java.io.BufferedReader in .... > >>>> ^java.io.BufferedWriter out ...] > >>>> .. > >>>> > >>>> Luc P. > >>>> > >>>> > Hey guys, > >>>> > > >>>> > I'm trying to read a lot of data, sometimes from *in* and sometimes > >>>> from a > >>>> > file. I extensively use the native .write and .read java methods. > >>>> > > >>>> > According to the clojure doc for reader, it says that "Default > >>>> > implementations always return a BufferedReader". However, when I > >>>> write, > >>>> > > >>>> > (*defn* solve [src dest] > >>>> > > >>>> > (*let* [in (clojure.java.io/reader src) > >>>> > > >>>> > out (clojure.java.io/writer dest) > >>>> > > >>>> > I get a bunch of reflection warnings on .read and .write, and most of > >>>> the > >>>> > running time is spent on reflection. AFAIK you can't type hint a > >>>> (let) > >>>> > construct, so what should I do here? > >>>> > > >>>> > Thanks! > >>> > >>> > >> -- > >> -- > >> You received this message because you are subscribed to the Google > >> Groups "Clojure" group. > >> To post to this group, send email to clo...@googlegroups.com<javascript:> > >> Note that posts from new members are moderated - please be patient with > >> your first post. > >> To unsubscribe from this group, send email to > >> clojure+u...@googlegroups.com <javascript:> > >> 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+u...@googlegroups.com <javascript:>. > >> For more options, visit https://groups.google.com/groups/opt_out. > >> > >> > >> > >> > >> -- > >> -- > >> You received this message because you are subscribed to the Google > >> Groups "Clojure" group. > >> To post to this group, send email to clo...@googlegroups.com<javascript:> > >> Note that posts from new members are moderated - please be patient with > >> your first post. > >> To unsubscribe from this group, send email to > >> clojure+u...@googlegroups.com <javascript:> > >> 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+u...@googlegroups.com <javascript:>. > >> For more options, visit https://groups.google.com/groups/opt_out. > >> > >> > >> > > > > > > > > -- > > Please correct me if I'm wrong or incomplete, > > even if you think I'll subconsciously hate it. > > > > > > -- > -- > 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/groups/opt_out. > > > -- Softaddicts<lprefonta...@softaddicts.ca> sent by ibisMail from my ipad! -- -- You received this message because you are subscribed to the Google Groups "Clojure" group. 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