commit 782b624edd671b2c913418b17bd365573d04017a
parent 4566ec687f1212d875c723019722a277ca93560e
Author: dwrz <dwrz@dwrz.net>
Date: Thu, 7 Feb 2019 03:13:50 +0000
Add elisp/rna-transcription
Diffstat:
3 files changed, 80 insertions(+), 0 deletions(-)
diff --git a/elisp/rna-transcription/README.md b/elisp/rna-transcription/README.md
@@ -0,0 +1,25 @@
+# Rna Transcription
+
+Given a DNA strand, return its RNA complement (per RNA transcription).
+
+Both DNA and RNA strands are a sequence of nucleotides.
+
+The four nucleotides found in DNA are adenine (**A**), cytosine (**C**),
+guanine (**G**) and thymine (**T**).
+
+The four nucleotides found in RNA are adenine (**A**), cytosine (**C**),
+guanine (**G**) and uracil (**U**).
+
+Given a DNA strand, its transcribed RNA strand is formed by replacing
+each nucleotide with its complement:
+
+* `G` -> `C`
+* `C` -> `G`
+* `T` -> `A`
+* `A` -> `U`
+## Source
+
+Rosalind [http://rosalind.info/problems/rna](http://rosalind.info/problems/rna)
+
+## Submitting Incomplete Solutions
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.
diff --git a/elisp/rna-transcription/rna-transcription-test.el b/elisp/rna-transcription/rna-transcription-test.el
@@ -0,0 +1,32 @@
+;;; rna-transcription-test.el --- Tests for RNA Transcription (exercism)
+
+;;; Commentary:
+
+
+;;; Code:
+
+(require 'cl)
+
+(load-file "rna-transcription.el")
+
+(ert-deftest transcribes-cytosine-to-guanine ()
+ (should (string= "G" (to-rna "C"))))
+
+(ert-deftest transcribes-guanine-to-cytosine ()
+ (should (string= "C" (to-rna "G"))))
+
+(ert-deftest transcribes-adenine-to-uracil ()
+ (should (string= "U" (to-rna "A"))))
+
+(ert-deftest transcribes-thymine-to-adenine ()
+ (should (string= "A" (to-rna "T"))))
+
+(ert-deftest it-transcribes-all-nucleotides ()
+ (should (string= "UGCACCAGAAUU"
+ (to-rna "ACGTGGTCTTAA"))))
+
+(ert-deftest it-validates-dna-strands ()
+ (should-error (to-rna "XCGFGGTDTTAA")))
+
+(provide 'rna-transcription-test)
+;;; rna-transcription-test.el ends here
diff --git a/elisp/rna-transcription/rna-transcription.el b/elisp/rna-transcription/rna-transcription.el
@@ -0,0 +1,23 @@
+;;; rna-transcription.el -- RNA Transcription (exercism)
+
+;;; Commentary:
+
+;;; Code:
+
+(provide 'rna-transcription)
+
+(defun transcribe (nucleotide)
+"Return the matching RNA pair for DNA NUCLEOTIDE."
+ (cond ((char-equal nucleotide ?C) "G")
+ ((char-equal nucleotide ?G) "C")
+ ((char-equal nucleotide ?A) "U")
+ ((char-equal nucleotide ?T) "A")
+ ((error "Unrecognized nucleotide"))))
+
+(defun to-rna (dna)
+"Transcribe a string representing DNA nucleotides.
+Return a string representing RNA nucleotides."
+ (cl-loop for nucleotide being the elements of dna
+ concat (transcribe nucleotide)))
+
+;;; rna-transcription.el ends here
