Exercism: "Rna Transcription in Clojure"

This is my solution to the Rna Transcription problem in Clojure:

	(ns dna)
	(defn to-rna [nucleotides]
	(let
	[transcribe
	(fn [nucleotide]
	(let [transcriptions {\C \G
	\G \C
	\A \U
	\T \A}
	transcribed (get transcriptions
	nucleotide)]
	(if (nil? transcribed)
	(throw (AssertionError.))
	transcribed)))]
	(apply str (map transcribe nucleotides))))

view raw dna.clj hosted with ❤ by GitHub

I used a map to look-up the transcription of each nucleotide.

The AssertionError exception was necessary to pass the provided tests. I would have rather used a different exception.

You can nitpick my solution here or see all the exercises I've done so far in this repository.

--------------------------------

Update:

After learning some new stuff, I've been able to simplify the code a bit more:

	(ns dna)
	(def ^:private transcriptions
	{\C \G
	\G \C
	\A \U
	\T \A})
	(defn- transcribe [nucleotide]
	(if-let
	[transcribed (get transcriptions nucleotide)]
	transcribed
	(throw (AssertionError.))))
	(defn to-rna [nucleotides]
	(apply str (map transcribe nucleotides)))

view raw dna2.clj hosted with ❤ by GitHub

I used the if-let form, def ^:private and the defn- macro in order to improve readability

You can nitpick this new version here.