javascript - 怎么在babel插件中编译异步回调结果？

Question

export default myplugin = ({ type:t }) => {
       let visitor = {
            stringLiteral ( path ) {
                  asyncfn(path, result =>{
                      // do something async
                      // how can i get these async result into ast tree?
                  })
            }
       }
       return {
            visitor
       }
}

https://github.com/babel/babel.github.io/issues/762

Answer 1

试过种种方法之后,我发现了deasync这个包，目前来说是可以实现异步转同步的

有什么副作用就不好说了

"use strict";
const deasync = require('deasync');

function asyncfn(callback){
    //...pipe(...).pipe(...).pipe(...).on("finish",()=>callback(null,"haha"))
}

let asyncfnSync = deasync(asyncfn)

export default myplugin = ({ type:t }) => {
       let visitor = {
            stringLiteral ( path ) {
                let result = asyncfnSyny(path.node)
                //haha..
            }
       }
       return {
            visitor
       }
}

参考链接

• https://www.npmjs.com/package/deasync

• http://blog.csdn.net/xingqiliudehuanghun/article/details/44056151

Answer 2

如果需要异步转同步，Promise、Generator 和 Async 不是很好的解决方案么？

不知下面的代码是否对你有用。

const asyncfn = (node) => {
  return new Promise((resolve, reject) => {
    // balalala
    //...pipe(...).on( 'finish', () => resolve(null, 'haha') )
  });
};

export default myplugin = ({ type:t }) => {
  let visitor = {
    stringLiteral (path) {

      const getAsyncfnResult = async () => {
        const result = await asyncfn(path.node);
        // haha
      };

      getAsyncfnResult();

    }
  }
  return {
    visitor
  }
}