// Copyright 2024 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package dev.cel.common.navigation;

import dev.cel.common.ast.CelExpr.CelComprehension;

/**
 * Specifies the traversal order of AST navigation.
 *
 * <p>For call expressions, the target is visited before its arguments.
 *
 * <p>For comprehensions, the visiting order is as follows:
 *
 * <ol>
 *   <li>{@link CelComprehension#iterRange}
 *   <li>{@link CelComprehension#accuInit}
 *   <li>{@link CelComprehension#loopCondition}
 *   <li>{@link CelComprehension#loopStep}
 *   <li>{@link CelComprehension#result}
 * </ol>
 */
public enum TraversalOrder {
  PRE_ORDER,
  POST_ORDER
}
