Hi all just a question about function naming conventions - what does "^:export" mean within say '(defn ^:export go-cljs []' ?

and I've also seen functions that are protocol implementations start with "-" as in "-list"

@teamaverage: It means it'll survive advanced compilations. It's translated to a goog.exportSymbol IIRC

Ie. you can use that symbol (with namespace) to call from javascript even after advanced compilation and name munging

ah cool thanks

@teamaverage the - is a convention to denote that a function is from a protocol, and that there's a wrapper for that function in the namespace. I.e. it's kinda private"ish". Unless you're implementing the protocol.

I usually use it by default, because wrappers for your protocol functions are pretty useful.

What does this mean, exactly: #'some-symbol

Kind of hard to google

@escherize: http://stackoverflow.com/questions/12862607/what-does-symbol-notation-mean-in-clojure may help

i googled it by searching for “hash quote symbol clojure"

i’ve had good luck finding reader macros by typing out the words for the characters

Ah cool, so it returns the namespaced name of the some-symbol

kind of like a function pointer?

user> (defn call-a [] (#'a 1))
#'user/call-a
user> (def a inc)
#'user/a
user> (call-a)
2
user> (def a dec)
#'user/a
user> (call-a)
0

Is there a way to know what the most popular lein templates are?

@escherize: Just of your reference, #’symbol returns what’s called “Var”. One of the purpose of Var is to enable code reload

user=> (type #'a)
clojure.lang.Var

@escherize: Popular does not always mean its useful or good 😉

@escherize: I don’t know if you can get some stats with leiningen downloads like you’d do with rubygems but github stars is a way to get such a list https://github.com/search?o=desc&q=lein&s=stars&type=Repositories&utf8=%E2%9C%93

@escherize: Also, more general: Anything that starts with a # is a reader macro expanded by the reader. They all described here: http://clojure.org/reader (this should solve future googling problems)

https://yobriefca.se/blog/2014/05/19/the-weird-and-wonderful-characters-of-clojure/

Is a helpful companion to the reader page

I've got a couple of syntactic sugar questions

(at least I assume that's what these are)

how do I insert code gracefully into slack...

😛

(s/defn create-array-of-group-permission :- ArrayOfGroupPermission
  [group-permission :- GroupPermission]
  (let [array-of-group-permission (ArrayOfGroupPermission.)]
    (-> array-of-group-permission
        (.getGroupPermission)
        (.add group-permission))
    array-of-group-permission))

in this function

.getGroupPermission and .add

don't appear to be defined in this file anywhere

I'm assuming the "." prefixing the function name means something

same with ArrayOfGroupPermission., with a dot after

in this example, it is taking array-of-group-permission which is an instance of ArrayOfGroupPermission and calling getGroupPermission() on it

and then passing the output, and calling add(group-permission) on that.

so, getGroupPermission and add are instance methods of ArrayOfGroupPermission

@samueldev: Also: All the glory details here: http://clojure.org/java_interop

thanks folks!

so dot suffix = create new instance of class

dot suffix = call the instance function of said instantiated class

dot prefix** on that second one