Make PdtExpression.Empty public.

Assets/Cryville/Common/Pdt/PdtExpression.cs

@@ -7,6 +7,18 @@ namespace Cryville.Common.Pdt {
 	/// PDT expression.
 	/// </summary>
 	public class PdtExpression {
+		/// <summary>
+		/// The empty expression.
+		/// </summary>
+		public static readonly PdtExpression Empty;
+		static PdtExpression() {
+			var ins = new LinkedList<PdtInstruction>();
+			ins.AddLast(new PdtInstruction.PushConstant(
+				PdtInternalType.Number, BitConverter.GetBytes(1f)
+			));
+			Empty = new PdtExpression(ins);
+		}
+
 		internal LinkedList<PdtInstruction> Instructions;
 		/// <summary>
 		/// Whether the value of this expression is constant.
@@ -125,15 +137,6 @@ namespace Cryville.Common.Pdt {
 			{ '$', -1 },
 		};
 
-		static readonly PdtExpression _emptyexp;
-		static PdtInterpreter() {
-			var ins = new LinkedList<PdtInstruction>();
-			ins.AddLast(new PdtInstruction.PushConstant(
-				PdtInternalType.Number, BitConverter.GetBytes(1f)
-			));
-			_emptyexp = new PdtExpression(ins);
-		}
-
 		PdtExpToken GetToken() {
 			ws();
 			var result = new PdtExpToken {

Assets/Cryville/Common/Pdt/PdtInterpreter.cs

@@ -247,7 +247,7 @@ namespace Cryville.Common.Pdt {
 						break;
 					case ':':
 					case ';':
-						var exp = c == ';' ? _emptyexp : GetExp();
+						var exp = c == ';' ? PdtExpression.Empty : GetExp();
 						InterpretObjectInternal<PropertyListAttribute>(pcflag, type, pkey, result, type => _binder.ChangeType(exp, type, null));
 						break;
 					default: