old_contents: /**
   * Created by nuintun on 2015/5/5.
   */
  
  'use strict';
  
  var util = require('../util');
  var common = require('../common');
  
  function transport(vinyl, options){
    var id = common.transportId(vinyl, options);
    var deps = common.transportCssDeps(vinyl, options);
  
    // get code
    var code = '';
    var importStyle = util.parseAlias('import-style', options.alias);
  
    // get code
    deps.forEach(function (id){
      code += "require('" + id.replace(/'/g, '\\\'') + "');\n";
    });
  
    // push import-style module dependencies
    deps.push(importStyle);
  
    // import import
    code += "require('" + importStyle.replace(/'/g, '\\\'') + "')('"
      + vinyl.contents.toString()
        .replace(/\\/g, '\\\\') // replace ie hack: https://github.com/spmjs/spm/issues/651
        .replace(/'/g, '\\\'')
      + "');";
  
    vinyl.contents = new Buffer(util.wrapModule(id, deps, code));
  
    // add import style deps
    vinyl.package.dependencies.push(importStyle);
    vinyl.package.include.push({
      id: importStyle,
      path: util.resolve(importStyle, vinyl, options.wwwroot)
    });
  
    return vinyl;
  }
  
  /**
   * Exports module.
   */
  
  module.exports = util.plugin('css', transport);
  
new_contents: /**
   * Created by nuintun on 2015/5/5.
   */
  
  'use strict';
  
  var util = require('../util');
  var common = require('../common');
  
  function transport(vinyl, options){
    var id = common.transportId(vinyl, options);
    var deps = common.transportCssDeps(vinyl, options);
  
    // get code
    var code = '';
    var importStyle = util.parseAlias('import-style', options.alias);
  
    // get code
    deps.forEach(function (id){
      code += "require('" + id.replace(/'/g, '\\\'') + "');\n";
    });
  
    // push import-style module dependencies
    deps.push(importStyle);
  
    // import import
    code += "require('" + importStyle.replace(/'/g, '\\\'') + "')('"
      + vinyl.contents.toString()
        .replace(/\\/g, '\\\\') // replace ie hack: https://github.com/spmjs/spm/issues/651
        .replace(/'/g, '\\\'')
      + "');";
  
    vinyl.contents = new Buffer(util.wrapModule(id, deps, code));
  
    // add import style dependencies
    vinyl.package.dependencies.push(importStyle);
    vinyl.package.include.push({
      id: importStyle,
      path: util.resolve(importStyle, vinyl, options.wwwroot)
    });
  
    return vinyl;
  }
  
  /**
   * Exports module.
   */
  
  module.exports = util.plugin('css', transport);
  
subject: add print method