close #12: add MsBuild task for running IronMeta

.gitignore

@@ -1,5 +1,6 @@
 .vs
 Source/IronMeta.snk
+*.nupkg
 
 # Build Folders (you can keep bin if you'd like, to store dlls and pdbs)
 [Bb]in/

README.md

@@ -11,6 +11,13 @@ IronMeta is available on [NuGet](https://www.nuget.org/packages/IronMeta/).  To
 Once you have installed the NuGet package, add a grammar file with the extension .ironmeta to your project.  Then generate a C# class from it.  You can do this in two ways:
 
 - You can install a [Visual Studio extension](https://visualstudiogallery.msdn.microsoft.com/73263c7c-319f-4f9e-a05a-b493094a4eb0) that provides a custom tool for generating C# code from IronMeta files.  You must set the "Custom Tool" property of your IronMeta file to be `IronMetaGenerator`.  Then the C# code will be generated whenever your grammer file changes.  Syntax errors will appear in your Error List.
+- `IronMeta.Library.dll` contains an MsBuild task called "IronMetaGenerate".  A simple example of how to use this:
+
+      <UsingTask TaskName="IronMetaGenerate" AssemblyFile="path_to\IronMeta.Library.dll" />
+      <Target Name="BeforeBuild">
+        <IronMetaGenerate Input="MyParser.ironmeta" Output="MyParser.g.cs" Namespace="MyNamespace" Force="true" />
+      </Target>
+
 - A command-line program `IronMeta.exe` is included in the NuGet package, in the `tools` directory.  The program takes the following arguments:
   - `-o {output}` (optional): Specify the output file name (defaults to `{input}_.g.cs`).
   - `-n {namespace}` (optional): Specify the namespace to use for the generated parser (defaults to the name of the directory the input file is in).

Source/CommonAssemblyInfo.cs

@@ -8,4 +8,4 @@
 [assembly: AssemblyTrademark("")]
 [assembly: AssemblyCulture("")]
 [assembly: AssemblyVersion("4.2.*")]
-[assembly: AssemblyInformationalVersionAttribute("4.2.3")]
+[assembly: AssemblyInformationalVersionAttribute("4.2.4")]

Source/Library/IronMetaGenerate.cs

@@ -0,0 +1,50 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Text.RegularExpressions;
+using IronMeta.Generator;
+using Microsoft.Build.Framework;
+using Microsoft.Build.Utilities;
+
+namespace IronMeta
+{
+    /// <summary>
+    /// An MsBuild task for generating parsers.
+    /// </summary>
+    public class IronMetaGenerate : Task
+    {
+        [Required]
+        public string Input { get; set; }
+
+        public string Namespace { get; set; }
+
+        public string Output { get; set; }
+
+        public bool Force { get; set; }
+
+        static readonly Regex IronMetaFileName = new Regex(@"^(.*).ironmeta\s*$", RegexOptions.Compiled);
+
+        public override bool Execute()
+        {
+            if (string.IsNullOrWhiteSpace(Output))
+            {
+                var match = IronMetaFileName.Match(Input);
+                if (match.Success)
+                    Output = match.Groups[1].Value + ".g.cs";
+                else
+                    Output = Input + ".g.cs";
+            }
+
+            var result = CSharpShell.Process(Input, Output, Namespace, Force);
+            if (result.Success)
+                return true;
+
+            int num, offset;
+            result.MatchState.GetLine(result.ErrorIndex, out num, out offset);
+
+            Log.LogError("", "", "", Input, num, offset, num, offset, result.Error);
+            return false;
+        }
+    }
+}

Source/Library/Library.csproj

@@ -42,6 +42,10 @@
     <AssemblyOriginatorKeyFile>..\IronMeta.snk</AssemblyOriginatorKeyFile>
   </PropertyGroup>
   <ItemGroup>
+    <Reference Include="Microsoft.Build" />
+    <Reference Include="Microsoft.Build.Framework" />
+    <Reference Include="Microsoft.Build.Tasks.v4.0" />
+    <Reference Include="Microsoft.Build.Utilities.v4.0" />
     <Reference Include="System" />
     <Reference Include="System.Core" />
     <Reference Include="Verophyle.Regexp, Version=1.1.5684.13780, Culture=neutral, PublicKeyToken=74cddc3ca888ce35, processorArchitecture=MSIL">
@@ -59,6 +63,7 @@
     <Compile Include="Generator\IGenerator.cs" />
     <Compile Include="Generator\AstNode.cs" />
     <Compile Include="Generator\Parser.g.cs" />
+    <Compile Include="IronMetaGenerate.cs" />
     <Compile Include="Matcher\Matcher.cs" />
     <Compile Include="Matcher\MatchItem.cs" />
     <Compile Include="Matcher\MatchResult.cs" />