Fix incremental compile of *.4ml files.

Src/CommandLine/CommandLine.sln

@@ -7,6 +7,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "CommandLine", "CommandLine.
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Core", "..\Core\Core.csproj", "{1B5724EC-FFF1-48D7-A700-AD46F0150AFC}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FormulaCodeGeneratorTask", "..\Extensions\FormulaCodeGeneratorTask\FormulaCodeGeneratorTask.csproj", "{3B52B4F5-52F5-4E19-88CD-6A4A78EA0BF1}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|x64 = Debug|x64
@@ -31,6 +33,14 @@ Global
 		{1B5724EC-FFF1-48D7-A700-AD46F0150AFC}.Release|x64.Build.0 = Release|x64
 		{1B5724EC-FFF1-48D7-A700-AD46F0150AFC}.Release|x86.ActiveCfg = Release|x86
 		{1B5724EC-FFF1-48D7-A700-AD46F0150AFC}.Release|x86.Build.0 = Release|x86
+		{3B52B4F5-52F5-4E19-88CD-6A4A78EA0BF1}.Debug|x64.ActiveCfg = Debug|x64
+		{3B52B4F5-52F5-4E19-88CD-6A4A78EA0BF1}.Debug|x64.Build.0 = Debug|x64
+		{3B52B4F5-52F5-4E19-88CD-6A4A78EA0BF1}.Debug|x86.ActiveCfg = Debug|x86
+		{3B52B4F5-52F5-4E19-88CD-6A4A78EA0BF1}.Debug|x86.Build.0 = Debug|x86
+		{3B52B4F5-52F5-4E19-88CD-6A4A78EA0BF1}.Release|x64.ActiveCfg = Release|x64
+		{3B52B4F5-52F5-4E19-88CD-6A4A78EA0BF1}.Release|x64.Build.0 = Release|x64
+		{3B52B4F5-52F5-4E19-88CD-6A4A78EA0BF1}.Release|x86.ActiveCfg = Release|x86
+		{3B52B4F5-52F5-4E19-88CD-6A4A78EA0BF1}.Release|x86.Build.0 = Release|x86
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

Src/Extensions/FormulaCodeGeneratorTask/FormulaCodeGeneratorTask.Targets

@@ -7,11 +7,12 @@
     <FormulaCodeGeneratorPath>$(MSBuildThisFileDirectory)\bin\$(FormulaCodeGeneratorBin)\FormulaCodeGeneratorTask.dll</FormulaCodeGeneratorPath>
   </PropertyGroup>  
   <UsingTask TaskName="FormulaCodeGeneratorTask.FormulaCodeGeneratorTask" AssemblyFile="$(FormulaCodeGeneratorPath)"/>
-  <Target Name="BeforeBuild">                                                            
+  <Target Name="BeforeBuild" Outputs="@(FormulaGenFiles->'%(FullPath).g.cs')">                                                            
     <ItemGroup>
       <FormulaGenFiles Include="@(EmbeddedResource->'%(FullPath)')" Condition="'%(EmbeddedResource.Generator)' == 'FormulaCodeGenerator'" />
     </ItemGroup>
     <Error Condition="!Exists($(FormulaCodeGeneratorPath))" Text="### Please build $(FormulaCodeGeneratorPath)"  />
-    <FormulaCodeGeneratorTask GeneratorInputs="@(FormulaGenFiles->'%(FullPath),%(CustomToolNamespace),%(IsThreadSafe),%(IsObjectGraph),%(IsNewOnly)')" DefaultNamespace="$(RootNamespace)" />
+    <FormulaCodeGeneratorTask GeneratorInputs="@(FormulaGenFiles->'%(FullPath),%(CustomToolNamespace),%(IsThreadSafe),%(IsObjectGraph),%(IsNewOnly)')"
+                              DefaultNamespace="$(RootNamespace)" /> 
   </Target>
 </Project>

Src/Extensions/FormulaCodeGeneratorTask/GenerateItem.cs

@@ -56,9 +56,11 @@
             IsObjectGraph = isObjectGraph.Trim().ToUpperInvariant() != "FALSE";
             IsNewOnly = isNewOnly.Trim().ToUpperInvariant() != "FALSE";
         }
-
+        
         public bool Generate(FormulaCodeGeneratorTask genTask)
         {
+            var outputFile = InputFile + ".g.cs";
+
             var env = new Env();
             try
             {
@@ -124,7 +126,6 @@
                     return true;
                 }
 
-                var outputFile = InputFile + ".g.cs";
                 try
                 {
                     var outInfo = new System.IO.FileInfo(outputFile);

Src/Extensions/FormulaCodeGeneratorTask/Task.cs

@@ -24,6 +24,25 @@
             set;
         }
 
+        public string[] Outputs {
+            get
+            {
+                List<string> outputs = new List<string>();
+                var inputs = GeneratorInputs.Split(inputSplits, StringSplitOptions.None);
+                foreach (var input in inputs)
+                {
+                    var parameters = input.Split(paramSplits, StringSplitOptions.None);
+                    if (parameters.Length > 0)
+                    {
+                        string inputFile = parameters[0];
+                        var outputFile = inputFile + ".g.cs";
+                        outputs.Add(outputFile);
+                    }
+                }
+                return outputs.ToArray();
+            }
+        }
+        
         public override bool Execute()
         {
             var inputs = GeneratorInputs.Split(inputSplits, StringSplitOptions.None);

Tst/Tests/API/LittleFuncLang/LittleFuncLang.4ml

@@ -14,7 +14,7 @@
                  parent: Subexpr + { NIL }, 
                  loc: { LEFT, RIGHT, NIL }, 
                  let: Subexpr + { NIL }). 
-                 
+                   
     Subexpr(e, p, l, t) :- 
             e is Expr, p = NIL, l = NIL, t = NIL;
             p is Subexpr, e = p.expr.arg1, l = LEFT,  t = p.let;