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to RNA Transcription in the Erlang Track

Published at Apr 02 2021 · 0 comments
Test suite

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

Running tests

In order to run the tests, issue the following command from the exercise directory:

For running the tests provided, rebar3 is used as it is the official build and dependency management tool for erlang now. Please refer to the tracks installation instructions on how to do that.

In order to run the tests, you can issue the following command from the exercise directory.

$ rebar3 eunit


For detailed information about the Erlang track, please refer to the help page on the Exercism site. This covers the basic information on setting up the development environment expected by the exercises.


Hyperphysics http://hyperphysics.phy-astr.gsu.edu/hbase/Organic/transcription.html

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.


%% Generated with 'testgen v0.2.0'
%% Revision 1 of the exercises generator was used
%% https://github.com/exercism/problem-specifications/raw/42dd0cea20498fd544b152c4e2c0a419bb7e266a/exercises/rna-transcription/canonical-data.json
%% This file is automatically generated from the exercises canonical data.



'1_empty_rna_sequence_test_'() ->
    {"Empty RNA sequence",
     ?_assertMatch([], rna_transcription:to_rna([]))}.

'2_rna_complement_of_cytosine_is_guanine_test_'() ->
    {"RNA complement of cytosine is guanine",
     ?_assertMatch("G", rna_transcription:to_rna("C"))}.

'3_rna_complement_of_guanine_is_cytosine_test_'() ->
    {"RNA complement of guanine is cytosine",
     ?_assertMatch("C", rna_transcription:to_rna("G"))}.

'4_rna_complement_of_thymine_is_adenine_test_'() ->
    {"RNA complement of thymine is adenine",
     ?_assertMatch("A", rna_transcription:to_rna("T"))}.

'5_rna_complement_of_adenine_is_uracil_test_'() ->
    {"RNA complement of adenine is uracil",
     ?_assertMatch("U", rna_transcription:to_rna("A"))}.

'6_rna_complement_test_'() ->
    {"RNA complement",


to_rna(Strand) -> 
    fun(S) -> 
        case S of
          $G -> $C;
          $C -> $G;
          $T -> $A;
          $A -> $U

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