Re: Type hints and records
Tangentially: In this particular case, reflection isn't strictly necessary because toString is a method of Object. In theory, the compiler could special-case Object's methods and never do reflection, right? In practice, I don't know if it's worth the effort, although it's certainly a little surprising that (.toString thing) can be 100 times slower than (str thing), at least until you know what's going on there. - Chris -- 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
Re: Type hints and records
Thanks for the clarification. Just to clear up any confusion, the .toString example was just the simplest example I could think of that illustrated was I was seeing with regards to reflection and type hints :) On Oct 20, 4:22 am, Michael Fogus mefo...@gmail.com wrote: Another potential option is to implement a record toString method: (defrecord Rec [^Integer i] Object (toString [_] (str i))) (str (Rec. 42)) ;= 42 -- 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
Re: Type hints and records
You can't really fix that, because (:foo bar) means call function :foo on bar, and in general the function :foo returns Object. (.foo bar) says look at the Java object bar, and give me its foo member. Because there is a typehint on that, Clojure can know what return type to expect. On Oct 19, 2:40 pm, Casper Clausen casp...@gmail.com wrote: Thanks, that works nicely! Is it intended or just incidental that type hints are not retained using the :-notation? There doesn't seem to be much advantage to not including type hints when available. On Oct 11, 1:02 am, Stuart Halloway stuart.hallo...@gmail.com wrote: I am using a record to wrap a number of java classes, which I then access various properties on. I am trying to avoid reflection so I type have type hinted, however when accessing the values in the record the type hints are lost. It might look something like this (defrecord Rec [^Integer i]) (defn to-string [^Rec record] (.toString (:i record))) However the to-string function gives a reflection warning, even with the input the to function type hinted. Now I know that type hints don't survive across function boundaries, but is there no way to get a type hinted value from the record? Treat the record as a typed thing instead of as a map (note the dot instead of the colon). (defn to-string [^Rec record] (.toString (.i record))) That said, and not knowing exactly what you are doing, the following looks better to me: (defrecord Rec [^int i]) (defn to-string [^Rec record] (str (:i record))) Stu Stuart Halloway Clojure/corehttp://clojure.com -- 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
Type hints and records
I am using a record to wrap a number of java classes, which I then access various properties on. I am trying to avoid reflection so I type have type hinted, however when accessing the values in the record the type hints are lost. It might look something like this (defrecord Rec [^Integer i]) (defn to-string [^Rec record] (.toString (:i record))) However the to-string function gives a reflection warning, even with the input the to function type hinted. Now I know that type hints don't survive across function boundaries, but is there no way to get a type hinted value from the record? -- 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
Re: Type hints and records
I am using a record to wrap a number of java classes, which I then access various properties on. I am trying to avoid reflection so I type have type hinted, however when accessing the values in the record the type hints are lost. It might look something like this (defrecord Rec [^Integer i]) (defn to-string [^Rec record] (.toString (:i record))) However the to-string function gives a reflection warning, even with the input the to function type hinted. Now I know that type hints don't survive across function boundaries, but is there no way to get a type hinted value from the record? Treat the record as a typed thing instead of as a map (note the dot instead of the colon). (defn to-string [^Rec record] (.toString (.i record))) That said, and not knowing exactly what you are doing, the following looks better to me: (defrecord Rec [^int i]) (defn to-string [^Rec record] (str (:i record))) Stu Stuart Halloway Clojure/core http://clojure.com -- 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
