Dynamic function chaining in Clojure

Question

Is there any idiomatic way to do some thing similar to what the -> macro does, but with a dynamic list of functions?

I.e. apply every function in a vector to the output of the last function (all functions take one argument)

A. Webb · Accepted Answer · 2014-07-15 00:08:36Z

3

A typical idiom is

(reduce #(%2 %) init fns)

For example,

(reduce #(%2 %) 0 [inc #(* 40 %) inc inc]) 
;=> 42

answered Jul 15, 2014 at 0:08

A. Webb

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Comments

Thumbnail · Accepted Answer · 2014-07-16 14:10:59Z

2

You can use the build-in comp function. You will want something like:

(defn f [fns & args]
   (let [all-fns (apply comp (reverse fns))]
      (apply all-fns args)))

And use it like:

(f [+ -] 1 2 3)
; -6

Thumbnail

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answered Jul 14, 2014 at 21:51

DanLebrero

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As we're told that fns is a vector, prefer rseq to reverse?