编译后不需要的匿名函数

Question

I'm writing an interface layer with pure functions in ClojureScript, but I'm getting undesired results after compile. Simple parameterized functions work fine. The example:

(defn rev [s]
  (.. s (split "") (reverse) (join "")))

... will successfully generate function rev(s){return s.split("").reverse().join(""); } function rev(s){return s.split("").reverse().join(""); } , while, with more complex parameters, like [sa & [b]] , or with parametric polimorphism, it generates an anonymous function:

(defn substr
  ([s a b]
    (.. s (substr a b)))
  ([s a]
    (.. s (substr a))))

... generates: function (s,a,b){ switch(arguments.length){ case 2: return substr__2.call(this,s,a); case 3: return substr__3.call(this,s,a,b); } throw(new Error('Invalid arity: ' + arguments.length)); } function (s,a,b){ switch(arguments.length){ case 2: return substr__2.call(this,s,a); case 3: return substr__3.call(this,s,a,b); } throw(new Error('Invalid arity: ' + arguments.length)); } function (s,a,b){ switch(arguments.length){ case 2: return substr__2.call(this,s,a); case 3: return substr__3.call(this,s,a,b); } throw(new Error('Invalid arity: ' + arguments.length)); } .

It doesn't even work with (def substr (fn ... instead. How can I force a function to be named with defn ?

Answer 1

Use ^:export on your function if you are going to be calling it from javascript.

(defn ^:export substr
  ([s a b]
    (.. s (substr a b)))
  ([s a]
    (.. s (substr a))))

The compiler should then generate the name so that you can call it from javascript.

Answer 2

我通过将函数导出到JavaScript的Window全局对象来实现的：

(aset js/window "substr" stdlib.string/substr)