The Co javascript library for generator based flow-control of asynchronous tasks
Co is a javascript library for executing generators that yield asynchronous tasks, so that asynchronous code can be written in a more concise manner.
Questions tagged [co]
114 questions
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0 answers
Issue with mkdirp from fs-promise and co
I have a generator function that creates a directory and performs operations on it once done:
import co from 'co'
import map from 'lodash/fp/map'
import path from 'path'
import {mkdirp} from 'fs-promise'
import co from 'co'
export const…
vamsiampolu
- 5,355
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1 answer
Loosing parameters passed from co-wrapped function to another one
I'm using the latest co-module (4.6).
This is a Koa-middleware. Therefore it is already co() wrapped.
create: function * () {
try {
this.body = yield services.createIt({obj: true})
} catch (err) {
this.body = { "errors": err.details }
…
Hedge
- 13,498
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1 answer
Advantages of using co over async/await functions and compiling with babel
Co bills itself as a "stepping stone towards ES7 async/await", but I'm not really sure why I should use it over just writing async functions and using babel to compile. Are there any advantages and disadvantages to these approaches or is it just a…
Joe Bushell
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- 5
0
votes
1 answer
jshint logs missing semicolon after yield in co
I am using JSHint for linting and have encountered a problem when using co, within generator in yield statement I get ERROR: line 18 col 28 Missing semicolon.
co(function *() {
let orgAccounts = yield OrgAccount.findAll({accountId:…
0
votes
1 answer
Mongoose doesn't yield findeOne results in co
I'm using co and mongoose and I'd like to my asynchronous code look little more "synchronously" and - as far as I read - co library allows me use data from one yielded promise in another to avoid callback hell. It seems to work with mongoose save…
Jarosław Rewers
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1 answer
How do a I terminate a co.js loop after execution?
Whenever I run a co generator loop, nothing happens after execution the process just hangs. How do I terminate after completion?
co(function *() {
// code;
})
user157251
- 64,489
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1 answer
silent errors in mocha tests with generator functions
I want to unit test a function.
In that function I'm using Co with a generator function.
When an error occurs I catch it, and I call cb with the error
In my unit test I make a false assertion but mocha doesn't report it, it just times…
Ernie
- 922
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2 answers
Javascript.Run Multi promises Synchronously
I want to request a website for 40 times.
I want this to be synchronously, like 10 requests 4 times.
This is My code for 1 request - 40 times:
'use strict';
var request = require('request');
var co = require('co');
function callUrl(url) {
…
Catalin
- 248
- 2
- 12
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votes
1 answer
Codeigniter Array Display
I want to display values of an array, but it only displays one value of the array rather than all values of the array.
Model:
function get_subject_position($exam_id , $class_id , $subject_id ) {
$this->db->where('exam_id' , $exam_id);
…
4Jean
- 737
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1 answer
Proper way to create a co-sqlite3 db object outside of a middleware
I am trying to implement a db access layer within my koa application. This works fine:
var sqlite3 = require('co-sqlite3');
var services = require('./services/services');
app.use(function *(next){
this.db = yield sqlite3(services.file);
…
Angel Joseph Piscola
- 656
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0
votes
1 answer
Can't find an explanation for koa.js workshop solution, exercise number one
It has to be rather simple, but I can't understand the solution for the beginning exercise from koa workshop.
The test:
var co = require('co');
var assert = require('assert');
var fs = require('./index.js');
describe('.stats()', function () {
…
Georgy
- 2,002
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1 answer
catch reject from promise
I want to hold the error from func() reject, not direct to onError() by choise,
Before I always let func() resolve, and determine return result after yield func(),
if I want to direct to onError() use throw ..;
Wondering any better idea I can just…
user1575921
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1 answer
Javascript - Using generators instead of promises
suppose I have following functions:
var f1 = function() {
console.log('running f1');
return new Promise(function(res, rej) {
setTimeout(() => res('resolved_1!'), 1000);
});
};
var f2 = function(a) {
console.log('running f2…
Javad M. Amiri
- 424
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votes
3 answers
NodeJS generator never reaches a certain line?
I am using co to run a generator function that does some scraping and cleansing of data. However, I never reach a certain part of the code after a loop. Here's what my code looks like:
function*(){
var url = "mongodb://" + config.host + ":" +…
An SO User
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1 answer
using co and promises from sync code (mongoDB example)
How do I use co() wrapped functions to integrate with normal synchronous code?
For example I have co.wrapped this function that uses yield to call an async method on mongo:
let wrap = co.wrap(function* (collName) {
debug("collName", collName);
…
dcsan
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