asyncawait.js

"use strict"

function async(generatorsource) {
 return(new Proxy(generatorsource, {
  apply(target, that, inputs) {
   return(new Promise(function(resolve, reject) {
    let generator = Reflect.apply(target, that, inputs)
    function proceed(type = "next" || "throw", input) {
     try {
      let result
      if(type == "throw") {
       result = generator.throw(input)
      } else {
       result = generator.next(input)
      }
      if(result.done) {
       resolve(result.value)
      } else {
       Promise.resolve(result.value).then(function(result) {
        proceed("next", result)
       }).catch(function(error) {
        proceed("throw", error)
      }) }
     } catch(error) {
      reject(error)
    } }
    proceed("next")
  })) },
  get(target, key) {
   if(key == "toString") {
    return(function() {
     return(generatorsource.toString().replace("function*", "async function"))
    })
   } else {
    return(Reflect.get(target, key))
} } })) }