ChrisMarinos#77 Merge upstream changes

FSharpKoans.Core/KoanContainer.fs

@@ -21,7 +21,12 @@ let runKoans container =
         with
         | ex -> 
             let outcome = sprintf "%s failed." m.Name
-            Failure(outcome, ex.InnerException)
+            let ex = 
+                match ex.InnerException with
+                | null -> Some(ex)
+                | _ -> Some(ex.InnerException)
+
+            Failure(outcome, ex)
 
     container
     |> findKoanMethods

FSharpKoans.Core/KoanResult.fs

@@ -4,7 +4,7 @@ open System
 
 type KoanResult = 
     | Success of string
-    | Failure of string * Exception
+    | Failure of string * Option<Exception>
 with
     member this.Message =
         match this with

FSharpKoans.Test/RunningKoans.fs

@@ -37,13 +37,14 @@ let ``A failing koan returns its exception`` () =
         typeof<FailureContainer>
         |> KoanContainer.runKoans
         |> Seq.head
-
-    let ex = 
+         
+    let msg = 
         match result with
-        | Failure (_, ex) -> ex
-        | _ -> null
+        | Failure (_, Some(ex)) -> ex.Message
+        | Failure (_, None) -> "No Exception!"
+        | Success (s) -> s
 
-    Assert.AreEqual("expected failure", ex.Message)
+    Assert.AreEqual("expected failure", msg)
 
 [<Test>]
 let ``A failing koan returns a failure message`` () =

FSharpKoans/AboutTypeProviders.fs

@@ -8,6 +8,18 @@ open FSharpKoans.Core
 // F# Type Providers make things like processing data from a 
 // variety of providers easily done in a typed fashion.
 //
+// Type Providers Available
+//  * DbmlFile - http://msdn.microsoft.com/en-us/library/hh362326.aspx
+//  * EdmxFile - http://msdn.microsoft.com/en-us/library/hh362313.aspx
+//  * ODataService - http://msdn.microsoft.com/en-us/library/hh362325.aspx
+//  * SqlDataConnection - http://msdn.microsoft.com/en-us/library/hh362320.aspx
+//  * SqlEntityConnection - http://msdn.microsoft.com/en-us/library/hh362322.aspx
+//  * WsdlService - http://msdn.microsoft.com/en-us/library/hh362328.aspx
+//  * CSV - http://fsharp.github.io/FSharp.Data/library/CsvProvider.html
+//  * HTML - http://fsharp.github.io/FSharp.Data/library/HtmlProvider.html
+//  * JSON - http://fsharp.github.io/FSharp.Data/library/JsonProvider.html
+//  * XML - http://fsharp.github.io/FSharp.Data/library/XmlProvider.html
+//  * WorldBank - http://fsharp.github.io/FSharp.Data/library/WorldBank.html
 // 
 // For a more thorough introduction to TypeProviders
 // https://docs.microsoft.com/en-us/dotnet/fsharp/tutorials/type-providers/
@@ -16,36 +28,67 @@ open FSharpKoans.Core
 [<Koan(Sort = 23)>]
 module ``about type providers`` =
     open FSharp.Data
-    open System.IO
+    open System.IO
 
-    type Simple = CsvProvider<"data/Simple.csv">
+    type Simple = CsvProvider<"data/Stocks.csv">
 
-    let getContent =
-        use file = File.OpenRead("data/Simple.csv")
+    let getCsvContent =
+        use file = File.OpenRead("data/Stocks.csv")
         Simple.Load(file).Rows
-
+        |> Seq.toList  // this is kind of a cheat to get around the fact that the stream needs to be closed
 
     [<Koan>]
     let CountingLinesInACSV() =
         // you can count items with a sequence operation over the data
         let countOfItems = 
-            getContent
+            getCsvContent
             |> Seq.length
 
-        AssertEquality countOfItems __
+        AssertEquality countOfItems __ // fix this
 
 
     [<Koan>]
     let GetCsvContentAndPerformAProjection() = 
-        // you can do other transformations like projects in a typed fashion
-        let popularities = 
-            getContent
-            |> Seq.map (fun x -> x.Popularity) 
-            |> Seq.sort
-            |> Seq.toArray 
-
-        let sumOfPopularities = popularities |> Seq.sum
-
-        AssertEquality sumOfPopularities __
-
-        AssertEquality popularities __
+        // try transformations like projections in a typed fashion with a simple predicate 
+        // typed to the column name
+        let avgOpen = 
+            getCsvContent
+            // What column makes this work?
+            |> Seq.averageBy ( fun x -> x.Open ) // write this projection
+
+        AssertEquality 32.185217391304347826086956522m avgOpen
+
+    [<Koan>]
+    let RenameAColumnAndSeeACompileTimeBreak() =
+        // one of the benefits of type providers is that when the source changes, the compiler will tell you!
+
+        let avgAdjClose = 
+            getCsvContent
+            // Rename the CSV column "Adj Close" to "AdjustedClose" in data/Stocks.csv
+            // compile the code to see the code on the next line break
+            |> Seq.averageBy (fun x -> x.``Adj Close`` )
+
+        AssertEquality 32.175217391304347826086956522m avgAdjClose
+
+
+    type NugetStats = HtmlProvider<"https://www.nuget.org/packages/FSharp.Data">
+
+    // helper function to analyze version numbers from Nuget
+    let getMinorVersion (v:string) =  
+        System.Text.RegularExpressions.Regex(@"\d.\d").Match(v).Value
+
+    let getNugetStats =
+        NugetStats().Tables.``Version History``.Rows
+
+    [<Koan>]
+    let TypeProvidersExistForWebRequestsAsWell() =
+        // group by minor version and calculate download count
+
+        let stats = 
+          getNugetStats
+          |> Seq.groupBy (fun r -> 
+              getMinorVersion r.Version)
+          |> Seq.map (fun (k, xs) -> 
+            k, xs |> Seq.sumBy (fun x -> x.Downloads))
+
+        AssertEquality __ __

FSharpKoans/FSharpKoans.fsproj

@@ -5,8 +5,8 @@
     <Name>FSharpKoans</Name>
   </PropertyGroup>
   <ItemGroup>
-    <Content Include="data\Simple.csv">
-      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    <Content Include="data\Stocks.csv">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </Content>
     <Compile Include="AboutTypeProviders.fs" />
     <Compile Include="AboutAsserts.fs" />
@@ -32,8 +32,8 @@
     <Compile Include="AboutFiltering.fs" />
     <Compile Include="PathToEnlightenment.fs" />
   </ItemGroup>
-  <ItemGroup>
-    <PackageReference Include="FSharp.Data" Version="3.0.0-beta4" />
+  <ItemGroup>
+    <PackageReference Include="FSharp.Data" Version="3.0.0-beta4" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\FSharpKoans.Core\FSharpKoans.Core.fsproj" />

FSharpKoans/PathToEnlightenment.fs

@@ -14,17 +14,22 @@ match result with
     printfn ""
     printfn ""
     printfn "You have not yet reached enlightenment ..."
-    printfn "%s" ex.Message
+    printfn "%s" 
+        (match ex with
+        | None -> "No error message could be found!"
+        | Some(ex) -> ex.Message)
     printfn ""
     printfn "Please meditate on the following code:"
-    printfn "%s" ex.StackTrace
+    printfn ""
+    printfn "%s" 
+        (match ex with
+        | None -> "No stack trace could be found!"
+        | Some(ex) -> ex.StackTrace)
     Environment.ExitCode <- 1
-
+    
 printfn ""
 printfn ""
 printfn ""
 printfn ""
-(*
 printf "Press any key to continue..."
-System.Console.ReadKey() |> ignore
-*)
+System.Console.ReadKey() |> ignore

FSharpKoans/data/Stocks.csv

@@ -0,0 +1,24 @@
+Date,Open,High,Low,Close,Volume,Adj Close
+2012-03-30,32.40,32.41,32.04,32.26,31749400,32.26
+2012-03-29,32.06,32.19,31.81,32.12,37038500,32.12
+2012-03-28,32.52,32.70,32.04,32.19,41344800,32.19
+2012-03-27,32.65,32.70,32.40,32.52,36274900,32.52
+2012-03-26,32.19,32.61,32.15,32.59,36758300,32.59
+2012-03-23,32.10,32.11,31.72,32.01,35912200,32.01
+2012-03-22,31.81,32.09,31.79,32.00,31749500,32.00
+2012-03-21,31.96,32.15,31.82,31.91,37928600,31.91
+2012-03-20,32.10,32.15,31.74,31.99,41566800,31.99
+2012-03-19,32.54,32.61,32.15,32.20,44789200,32.20
+2012-03-16,32.91,32.95,32.50,32.60,65626400,32.60
+2012-03-15,32.79,32.94,32.58,32.85,49068300,32.85
+2012-03-14,32.53,32.88,32.49,32.77,41986900,32.77
+2012-03-13,32.24,32.69,32.15,32.67,48951700,32.67
+2012-03-12,31.97,32.20,31.82,32.04,34073600,32.04
+2012-03-09,32.10,32.16,31.92,31.99,34628400,31.99
+2012-03-08,32.04,32.21,31.90,32.01,36747400,32.01
+2012-03-07,31.67,31.92,31.53,31.84,34340400,31.84
+2012-03-06,31.54,31.98,31.49,31.56,51932900,31.56
+2012-03-05,32.01,32.05,31.62,31.80,45240000,31.80
+2012-03-02,32.31,32.44,32.00,32.08,47314200,32.08
+2012-03-01,31.93,32.39,31.85,32.29,77344100,32.29
+2012-02-29,31.89,32.00,31.61,31.74,59323600,31.74