public IEnumerable <MethodDeclaration> FindCandidatesViaRefactoringPermutations(TargetInfo left, MethodDeclaration right)
        {
            right = right.DeepCopy();

            /*
             * Steps to change one to match the other.
             *      Get the lookup table for left.
             *      Get the lookup table for right.
             *      Loop through left, renaming the corresponding right var as you go (don't worry about collisions yet).
             * Compare.
             *
             * This is essentially a normalization of one to the other.
             */
            Dictionary <string, List <LocalLookupVariable> > left_table  = left.GetLookupTableWithParams();
            Dictionary <string, List <LocalLookupVariable> > right_table = right.GetLookupTableWithParams();

            if (left_table.Keys.Count == right_table.Keys.Count)
            {
                IDictionary <string, string> renames = new Dictionary <string, string>();

                for (int i = 0; i < left_table.Count; i++)
                {
                    var left_var_name  = left_table.Keys.ToArray()[i];
                    var right_var_name = right_table.Keys.ToArray()[i];

                    // current name => new name
                    renames.Add(right_var_name, left_var_name);
                }

                RenameLocalVariableRefactoring r = new RenameLocalVariableRefactoring(renames);
                right.AcceptVisitor(r, null);

                yield return(right);
            }
        }
        private MethodDeclaration MakePermutation(MethodDeclaration right, IEnumerable <PrimExpSet> prim_groups)
        {
            ResetNameCount();

            right = right.DeepCopy();
            var rights_primitives = right.AllPrimitiveExpressions();

            foreach (var prim_grp in prim_groups)
            {
                var param_name = NextName();

                var typeRef = new TypeReference(prim_grp.ValueType.FullName);
                right.Parameters.Add(new ParameterDeclarationExpression(typeRef, param_name));

                var replacer = new PrimitiveReplacer();
                foreach (var pos in prim_grp.Positions)
                {
                    replacer.AddReplacement(rights_primitives[pos], new IdentifierExpression(param_name));
                }
                right.AcceptVisitor(replacer, null);
            }

            return(right);
        }