Asynchronous becomes synchronous with the yield
npm install yieldflow
var yieldflow = require('yieldflow');
var assert = require('assert');
function login(username, password, callback) {
assert(username);
assert(password);
assert(callback);
setTimeout(()=>callback(0), 1000);
}
function sendmsg(msg, callback) {
assert(msg);
setTimeout(()=>callback(msg), 500);
}
yieldflow(function* (next){
var code = yield login('user', '123', (code)=>{
next(code);
});
console.log('login: ' + code);
var sendText = yield sendmsg('xxx', (text)=>{
next(text);
});
console.log('send: ' + sendText);
sendText = yield sendmsg('fuck', (text)=> {
next(text);
});
console.log('send: ' + sendText);
});
result print:
login: 0
send: xxx
send: fuck
login and sendmsg is two asyns function.
yeildflow pass a next function to you, you will call next(result) in the async function callback to return the result to yield operation (var code = yield login(...);) and move one step.
Have fun.