callback

问题 I'm trying to wrap an async function up so that I can use it without importing asyncio in certain files. The ultimate goal is to use asynchronous functions but being able to call them normally and get back the result. How can I access the result from the callback function printing(task) and use it as the return of my make_task(x) function? MWE: #!/usr/bin/env python3.7 import asyncio loop = asyncio.get_event_loop() def make_task(x): # Can be used without asyncio task = loop.create_task(my

问题 I'm trying to wrap an async function up so that I can use it without importing asyncio in certain files. The ultimate goal is to use asynchronous functions but being able to call them normally and get back the result. How can I access the result from the callback function printing(task) and use it as the return of my make_task(x) function? MWE: #!/usr/bin/env python3.7 import asyncio loop = asyncio.get_event_loop() def make_task(x): # Can be used without asyncio task = loop.create_task(my

问题 I'm sorry i couldn't find a better title. I'm trying to achieve something like the following abstract class Person case class User(uid: String, firstname: String, active: String) extends Person case class Admin(id: String, pseudo: String, securityClearance: String) extends Person def innerFunctionForUser(user: User): List[String] = { List() :+ user.uid :+ user.firstname :+ user.active } def innerFunctionForAdmin(admin: Admin): List[String] = { List() :+ admin.id :+ admin.psuedo :+ admin

问题 This question already has answers here : How do I return the response from an asynchronous call? (39 answers) Closed 9 days ago . I have this function: function doStuff(range, file) { var fr = new FileReader(); var hash = ''; fr.onload = function (e) { var out = "stuff happens here"; hash = asmCrypto.SHA256.hex(out); return hash; }; fr.readAsArrayBuffer(file); return hash; } Right now, the function completes before the onload event is finished, so doStuff always returns "". I think a callback

问题 Is it possible to write a python script such that a function is called whenever a USB device is added or removed on Windows? libusb (and corresponding python modules such as libusb1) appears to be the most popular solution, but it lacks hotplugging callback registration support in Windows. A feature request has been open for this since 2015, and it's still not implemented. I've seen some hacks query Windows' usb devices at some interval, do a diff of the current list of devices from the

问题 Is it possible to run a chord callback even if the main tasks failed? I've created a chord which I added a bunch of tasks and registered a callback to it. My problem, is that if one of the tasks fail the callback is not triggered, but I would like the callback to be triggered either way. I've tried to register the callback with si() (immutability) callback = tasks.run_delete_rule.si([timestamp]) header = [tasks.run_update_rule.s(i, timestamp) for i in item_ids] result = chord(header)(callback

问题 I have a constructor function which registers an event handler: function MyConstructor(data, transport) { this.data = data; transport.on('data', function () { alert(this.data); }); } // Mock transport object var transport = { on: function(event, callback) { setTimeout(callback, 1000); } }; // called as var obj = new MyConstructor('foo', transport); However, I'm not able to access the data property of the created object inside the callback. It looks like this does not refer to the object that

问题 I'm creating a matlab application without a gui, and I'm pretty new to action events and callbacks. I can only find documentation regarding action events that either use the gui, or create a listener that is called upon the program hitting an if statement. I'd like to be able to use action events dynamically, and have them be called whenever a specific condition is met. Is there a way to do this? 来源： https://stackoverflow.com/questions/62087345/actionevents-in-matlab-without-if-statements

问题 I'm wondering why add_action( 'admin_post_nopriv_myAction', 'myCallback' ); does not fire when I add it inside a function, but it does work when added outside a function. See examples below. I minimized the code a bit to show the idea. In reality a form is output in the shortcode function and processed in the callback. This one does not fire the callback: function my_shortcode() { add_action( 'admin_post_nopriv_myAction', 'myCallback' ); add_action( 'admin_post_myAction', 'myCallback' );

问题 I'm trying to understand the differences between es6 promises and regular callbacks but don't get the examples below. Can someone show what it would look like to do the below with callbacks? // an immediately resolved promise var p2 = Promise.resolve("foo"); // can get it after the fact, unlike events p2.then((res) => console.log(res)); var p = new Promise(function(resolve, reject) { setTimeout(() => resolve(4), 2000); }); // handler can't change promise, just value p.then((res) => { res += 2