1 files changed, 57 insertions, 0 deletions
diff --git a/src/runtime/dotNet/Expr/Application.cs b/src/runtime/dotNet/Expr/Application.cs
new file mode 100644
index 000000000..bcfb309a5
--- /dev/null
+++ b/src/runtime/dotNet/Expr/Application.cs
@@ -0,0 +1,57 @@
+using System;
+using System.Runtime.InteropServices;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace PGFSharp
+{
+	public class ApplicationExpr : Expr
+	{
+		public override R Accept<R> (IVisitor<R> visitor)
+		{
+			var args = new List<Expr> ();
+			var expr = this;
+			while (expr.Function is ApplicationExpr) {
+				args.Add (expr.Argument);
+				expr = expr.Function as ApplicationExpr;
+			}
+			args.Add (expr.Argument);
+			if (!(expr.Function is FunctionExpr))
+				throw new ArgumentException ();
+
+			args.Reverse ();
+			return visitor.VisitApplication ((expr.Function as FunctionExpr).Name, args.ToArray());
+		}
+		
+		[StructLayout(LayoutKind.Sequential)]
+		private struct PgfExprApp {
+			public IntPtr Function;
+			public IntPtr Argument;
+		}
+
+		private PgfExprApp Data => Marshal.PtrToStructure<PgfExprApp>(DataPtr);
+
+		public Expr Function => Expr.FromPtr(Data.Function, _pool);
+		public Expr Argument => Expr.FromPtr(Data.Argument, _pool);
+
+		internal ApplicationExpr(IntPtr ptr, NativeGU.NativeMemoryPool pool) : base(ptr, pool) {	}
+		public ApplicationExpr(string fname, IEnumerable<Expr> args)
+		{
+			_pool = new NativeGU.NativeMemoryPool();
+			MkStringVariant((byte)PgfExprTag.PGF_EXPR_FUN, fname, ref _ptr);
+			foreach (var arg in args) {
+				var fun = _ptr;
+				var exprApp = NativeGU.gu_alloc_variant((byte)PgfExprTag.PGF_EXPR_APP,
+					(UIntPtr)Marshal.SizeOf<PgfExprApp>(), UIntPtr.Zero, ref _ptr, _pool.Ptr);
+
+				Native.EditStruct<PgfExprApp> (exprApp, (ref PgfExprApp app) => {
+					app.Function = fun;
+					app.Argument = arg.Ptr;
+				});
+			}
+
+
+		}
+	}
+}
+