Variable

- When calling `replace(Statement, Statement)`, if we hit the `variableAssignment` replacement check, first check and ensure it is not null`, try

source/tlang/compiler/symbols/data.d

@@ -508,11 +508,16 @@ public class Variable : TypedEntity, MStatementSearchable, MStatementReplaceable
             assignment = cast(VariableAssignment)that;
             return true;
         }
-        /* Recurse on the variable assignment */
-        else
+        /* Recurse on the variable assignment (if there is one) */
+        else if(assignment !is null)
         {
             return assignment.replace(thiz, that);
         }
+        /* Exhausted all possibilities */
+        else
+        {
+            return false;
+        }
     }
 
     /**