traceur/src/codegeneration/module/ModuleSpecifierVisitor.js

ES6 to ES5 compiler

// Copyright 2012 Traceur Authors.
//
// 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
//
//      http://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.

import {ParseTreeVisitor} from '../../syntax/ParseTreeVisitor.js';
import {StringSet} from '../../util/StringSet.js';

// TODO(arv): This is closer to the ModuleVisitor but we don't care about
// modules.

/**
 * Visits a parse tree and finds all ModuleSpecifiers in it.
 *
 *   import * as m from "url"
 */
export class ModuleSpecifierVisitor extends ParseTreeVisitor {

  constructor(options) {
    super();
    this.options_ = options;
    this.moduleSpecifiers_ = new StringSet();
  }

  get moduleSpecifiers() {
    return this.moduleSpecifiers_.valuesAsArray();
  }

  visitModuleSpecifier(tree) {
    this.moduleSpecifiers_.add(tree.token.processedValue);
  }
}