From c190ef5d5d9cc33e2085622910f8e1131e1d6000 Mon Sep 17 00:00:00 2001
From: Markus Bertheau <mbertheau@gmail.com>
Date: Fri, 22 May 2015 23:22:05 +0200
Subject: [PATCH] Add rna transcription exercise

---
 config.json                                  |  3 ++-
 rna-transcription/example.rkt                | 12 ++++++++++++
 rna-transcription/rna-transcription-test.rkt | 16 ++++++++++++++++
 3 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 rna-transcription/example.rkt
 create mode 100644 rna-transcription/rna-transcription-test.rkt

diff --git a/config.json b/config.json
index 6dc26b3..f2a0ed4 100644
--- a/config.json
+++ b/config.json
@@ -4,6 +4,7 @@
   "repository": "https://github.com/exercism/xracket",
   "active": false,
   "problems": [
-    "bob"
+    "bob",
+    "rna-transcription"
   ]
 }
diff --git a/rna-transcription/example.rkt b/rna-transcription/example.rkt
new file mode 100644
index 0000000..133271e
--- /dev/null
+++ b/rna-transcription/example.rkt
@@ -0,0 +1,12 @@
+#lang racket
+
+(define (to-rna sequence)
+  (list->string
+    (for/list ([c (in-string sequence)])
+      (case c
+        [(#\G) #\C]
+        [(#\C) #\G]
+        [(#\T) #\A]
+        [(#\A) #\U]))))
+
+(provide to-rna)
diff --git a/rna-transcription/rna-transcription-test.rkt b/rna-transcription/rna-transcription-test.rkt
new file mode 100644
index 0000000..12f886a
--- /dev/null
+++ b/rna-transcription/rna-transcription-test.rkt
@@ -0,0 +1,16 @@
+#lang racket
+
+(require rackunit
+         rackunit/text-ui
+        "rna-transcription.rkt")
+
+(define suite
+  (test-suite
+    "Tests for the rna-transcription exercise"
+    (check-equal? (to-rna "G") "C" "transcribes guanine to cytosine")
+    (check-equal? (to-rna "C") "G" "transcribes cytosine to guanine")
+    (check-equal? (to-rna "T") "A" "transcribes thymine to adenine")
+    (check-equal? (to-rna "A") "U" "transcribes adenine to uracil")
+    (check-equal? (to-rna "ACGTGGTCTTAA") "UGCACCAGAAUU" "transcribes all occurences")))
+
+(exit (if (zero? (run-tests suite)) 0 1))