port from perforce

intromat/Intromat/Nodes/Code/LiteralValueBase.cs

@@ -0,0 +1,28 @@
+using System.Text;
+using Intromat.Model.Compiler;
+
+namespace Intromat.Nodes.Code
+{
+    public abstract class LiteralValueBase<T> : ITypedExpression<T>
+    {
+        public virtual string? PreviewValue => Value?.ToString();
+
+        public T ParentValue { get; set; } = default!;
+
+        public T InputValue { get; set; } = default!;
+
+        public T Value { get; set; } = default!;
+
+        public ERelativeSource RelativeSource { get; set; }
+
+        public virtual void Compile(CompilerContext context, StringBuilder sb)
+        {
+            sb.Append(Value);
+        }
+
+        public virtual T Evaluate()
+        {
+            return Value;
+        }
+    }
+}