Minor cleanup of Program.fs, input/output handling.

Lbac.Compiler/Part01-Introduction.fs

@@ -3,7 +3,7 @@
     open System
     open System.IO
 
-    type Cradle(keyReader: unit -> char, output : TextWriter) as x =
+    type Cradle(input : TextReader, errorWriter : TextWriter) as x =
         let mutable _look = '\u0000'
         let tab = "\t"
 
@@ -16,11 +16,11 @@
             and set value = _look <- value
 
         member x.getChar() = 
-            x.look <- char( keyReader() )
+            x.look <- char( input.Read() )
 
         member x.error(s : string) = 
-            output.WriteLine()
-            output.WriteLine("Error: {0}.", s)
+            errorWriter.WriteLine()
+            errorWriter.WriteLine("Error: {0}.", s)
 
         member x.abort(s : string) =
             x.error(s)

Lbac.Compiler/Part02-ExpressionParsing.fs

@@ -4,8 +4,8 @@
     open System.IO
     open IL
 
-    type ExpressionParsing(keyReader: unit -> char, output : TextWriter) = 
-        inherit Cradle(keyReader, output)
+    type ExpressionParsing(input : TextReader, errorWriter : TextWriter) = 
+        inherit Cradle(input, errorWriter)
 
 // Introduced later, but F# likes it above members.
 

Lbac.Compiler/Program.fs

@@ -8,22 +8,15 @@ let run(reader, writer) =
     parser.expression()
 
 let runInteractive() = 
-    let outputStream = Console.Out
-    let keyReader() = 
-        let cki = Console.ReadKey()
-        cki.KeyChar
-    let il = run(keyReader, outputStream)
+    let il = run(Console.In, Console.Error)
     printfn "%A" il
     Console.ReadLine() |> ignore
 
 
 let runWithFiles inFile outFile = 
-    let outputStream = Console.Out
     let input = File.ReadAllText(inFile)
     let reader = new StringReader(input)
-    let charReader() = 
-        Convert.ToChar(reader.Read())    
-    let il = run(charReader, outputStream)
+    let il = run(reader, Console.Error)
     let moduleName = match outFile with
                      | Some s -> s
                      | None   -> IO.Path.ChangeExtension(inFile, ".exe")
@@ -34,10 +27,9 @@ let runWithFiles inFile outFile =
 let main(args) = 
     let arguments = CommandLine.parse(Array.append [|"Lbac.Compiler.exe"|]  args, Console.Out, Console.Error)
     if arguments.Valid then 
-        if arguments.InFile.IsSome then
-            runWithFiles arguments.InFile.Value arguments.OutFile
-        else 
-            runInteractive()
+        match arguments.InFile with
+        | Some filename -> runWithFiles filename arguments.OutFile
+        | _             -> runInteractive()
         0
     else
         1

Lbac.Tests.FSharp/Part01Tests.fs

@@ -11,9 +11,8 @@
         member x.testInit() = 
             let actual = new StringBuilder()
             let sw = new StringWriter(actual)
-            let kr() = '1';
 
-            let cradle = new Cradle(kr, sw)
+            let cradle = new Cradle(new StringReader("1"), sw)
 
             // the introduction "cradle" code doesn't actually do anything.
             Assert.AreEqual("", actual.ToString())

Lbac.Tests.FSharp/Part02Tests.fs

@@ -12,22 +12,15 @@
             let actual = new StringBuilder()
             let sw = new StringWriter(actual)
             let sr = new StringReader(input)
-            let kr() = 
-                let c = sr.Read()
-                match c with 
-                    | -1 -> 
-                    '\u0000'
-                    | _  -> System.Convert.ToChar(c);
-            let parser = new ExpressionParsing(kr, sw)
+            let parser = new ExpressionParsing(sr, sw)
             let il = parser.expression()
             IL.execute<System.Int32> (il, None) // change false to true to save assembly to disk -- useful for running PEVerify.
 
         [<TestMethod>]
         member x.testTerm() = 
             let actual = new StringBuilder()
             let sw = new StringWriter(actual)
-            let kr() = '1';
-            let parser = new ExpressionParsing(kr, sw)
+            let parser = new ExpressionParsing(new StringReader("1"), sw)
 
             let actual = parser.term()
             let arg = match actual.Head with