old_contents: 'use strict';
  
  var fs = require('fs');
  
  /**
   * Check the existence of the file
   */
  function checkFileExistsSync(filepath){
    let flag = true;
  
    try {
      fs.accessSync(filepath, fs.F_OK);
    } catch(e){
      flag = false;
    }
  
    return flag;
  };
  
  module.exports = {
   checkFileExistsSync: checkFileExistsSync
  };
  
new_contents: 'use strict';
  
  var fs = require('fs');
  
  /**
   * Check the existence of the file
   */
  function checkFileExistsSync(filepath){
    var flag = true;
  
    try {
      fs.accessSync(filepath, fs.F_OK);
    } catch(e){
      flag = false;
    }
  
    return flag;
  };
  
  module.exports = {
   checkFileExistsSync: checkFileExistsSync
  };
  
subject: Use var rather than let for pre-ES6 cross-compatibility