Add is function.

Assets/Cryville/Common/Pdt/PdtVariableMemory.cs

@@ -4,7 +4,7 @@ namespace Cryville.Common.Pdt {
 	/// <summary>
 	/// Span on the memory of a <see cref="PdtEvaluatorBase" />.
 	/// </summary>
-	public unsafe struct PdtVariableMemory {
+	public unsafe struct PdtVariableMemory : IEquatable<PdtVariableMemory> {
 		readonly byte* _ptr;
 		/// <summary>
 		/// The length of the span.
@@ -46,6 +46,14 @@ namespace Cryville.Common.Pdt {
 			for (int i = 0; i < length; i++)
 				dest[destOffset + i] = _ptr[i];
 		}
+		/// <inheritdoc />
+		public bool Equals(PdtVariableMemory obj) {
+			if (Type != obj.Type || Length != obj.Length) return false;
+			for (int i = 0; i < Length; i++) {
+				if (*(_ptr + i) != *(obj._ptr + i)) return false;
+			}
+			return true;
+		}
 		/// <summary>
 		/// Gets the memory of the span as a number.
 		/// </summary>