RNA problem done

exercism/fsharp/rna-transcription/README.md

+# 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`
+
+## Hints
+For this exercise the following F# feature comes in handy:
+- [Match Expressions](https://fsharpforfunandprofit.com/posts/match-expression/) While this can be solved using a dictionary, using a match expression is more idiomatic.
+
+## Running the tests
+
+To run the tests, run the command `dotnet test` from within the exercise directory.
+
+## Autoformatting the code
+
+F# source code can be formatted with the [Fantomas](https://github.com/fsprojects/fantomas) tool.
+
+After installing it with `dotnet tool restore`, run `dotnet fantomas .` to format code within the current directory.
+
+## Further information
+
+For more detailed information about the F# track, including how to get help if
+you're having trouble, please visit the exercism.io [F# language page](http://exercism.io/languages/fsharp/resources).
+
+## Source
+
+Hyperphysics [http://hyperphysics.phy-astr.gsu.edu/hbase/Organic/transcription.html](http://hyperphysics.phy-astr.gsu.edu/hbase/Organic/transcription.html)
+

exercism/fsharp/rna-transcription/RnaTranscription.fs

+module RnaTranscription
+
+let toRna (dna: string): string =
+    dna
+    |> String.map (fun x ->
+        match x with
+        | 'G' -> 'C'
+        | 'C' -> 'G'
+        | 'T' -> 'A'
+        | 'A' -> 'U'
+        | _ -> ' ')

exercism/fsharp/rna-transcription/RnaTranscription.fsproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp3.0</TargetFramework>
+
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <Compile Include="RnaTranscription.fs" />
+    <Compile Include="RnaTranscriptionTests.fs" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.6.1" />
+    <PackageReference Include="xunit" Version="2.4.1" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.1" />
+    <PackageReference Include="FsUnit.xUnit" Version="3.8.1" />
+  </ItemGroup>
+
+</Project>

exercism/fsharp/rna-transcription/RnaTranscriptionTests.fs

+// This file was auto-generated based on version 1.3.0 of the canonical data.
+
+module RnaTranscriptionTests
+
+open FsUnit.Xunit
+open Xunit
+
+open RnaTranscription
+
+[<Fact>]
+let ``Empty RNA sequence`` () =
+    toRna "" |> should equal ""
+
+[<Fact>]
+let ``RNA complement of cytosine is guanine`` () =
+    toRna "C" |> should equal "G"
+
+[<Fact>]
+let ``RNA complement of guanine is cytosine`` () =
+    toRna "G" |> should equal "C"
+
+[<Fact>]
+let ``RNA complement of thymine is adenine`` () =
+    toRna "T" |> should equal "A"
+
+[<Fact>]
+let ``RNA complement of adenine is uracil`` () =
+    toRna "A" |> should equal "U"
+
+[<Fact>]
+let ``RNA complement`` () =
+    toRna "ACGTGGTCTTAA" |> should equal "UGCACCAGAAUU"
+