Jay Fields is a software developer at DRW Trading. He has a passion for discovering and maturing innovative solutions. His most recent work has been in the Domain Specific Language space where he's delivered applications that empowered subject matter experts to write the business rules of the applications. He is also very interested in maturing software design through software testing. Jay is a DZone MVB and is not an employee of DZone and has posted 116 posts at DZone. You can read more from them at their website. View Full User Profile

Clojure: name Function

06.22.2012
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The 'name' function is a clojure function that returns the string for a keyword, symbol, or string.
name - function
Usage: (name x)
Returns the name String of a string, symbol or keyword.
At first glace this might not seem that interesting; however, it's good to know 'name' if you've ever been surprised by (str :foo) => ":foo". If you have a ruby background (as I do), you probably expected the result to be "foo", spent a bit of time looking, and found that (name :foo) was actually what you were looking for.

That's helpful, but not particularly exciting. Perhaps a more interesting application of name is the ability to normalize all keys as strings and destructure. For example, say you're designing a library that monitors threads and you want to be able to pass in warning and error thresholds. Usage of your functions may look like the following examples
(monitored-threads/create :warn-threshold 100 :error-threshold 200)
(monitored-threads/create "warn-threshold" 100 "error-threshold" 200)
Assuming a simple function that updates keys:
(defn update-keys [m f]
  (reduce (fn [r [k v]] (assoc r (f k) v)) {} m))
You can now write your create function as:
(defn create [& {:as m}]
  (let [{:strs [warn-threshold error-threshold]} (update-keys m name)]
    ; do work, son
    ))
Published at DZone with permission of Jay Fields, author and DZone MVB. (source)

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