It's sends 4 times the amount of members - node.js

Question

So I want my bot in a certain server to send a dm to a random member every 10 minutes. And when my bot has sent everyone from the server a dm it sends a complete message.
But when i start the bot it sends 4 times the amount of members
if (message.content.startsWith(botconfig.prefix + 'dmall')) {
console.log("demo");
var list = message.guild.members.array();
sendMessage(list);
}
});
function sendMessage(list) {
setTimeout(function () {
for (i = 0; i < list.length; i++) {
console.log(list.length);
}
console.log("I'm done, mate!");
sendMessage(list);
}, 10 * 1000);
}
CONSOLE:
demo
4 (is the amount of the members)
4
4
4
I'm done mate!

Answer 1

This part of your code:
for (i = 0; i < list.length; i++) {
console.log(list.length);
}
tells Javascript to run the statement:
console.log(list.length);
list.length times. If list.length is 4 which it appears to be here, then you will see in the console
4
4
4
4
That's what the code was instructed to do.
I don't see any reason why you'd put that in a loop unless you want to output each array element separately. So, if you want to just output the length once, then replace this:
for (i = 0; i < list.length; i++) {
console.log(list.length);
}
with this:
console.log(list.length);
In addition, if you were to use a for loop, you MUST declare all variables that you use. So, this:
for (i = 0; i < list.length; i++) {
is very dangerous. It relies on a higher scoped i which can easily conflict with other higher scoped i variables and create hard-to-figure out bugs. Every for loop should declare it's own loop variable as in:
for (let i = 0; i < list.length; i++) {
If you run your code in strict mode (which you should), the above for loop declaration would likely cause an error (which is a good thing because you'd immediately see the coding error and fix it).

Answer 2

There are a couple of things wrong here.
For of: JavaScript variable scoping messing you up (Different example here
Second of all: setTimeout is not the same as setInterval.
Completely fixing your issue would be:
// Use the discord API
let users = ['justme']
function getUsers() {
// Mutate just to display a new one each time
users = [...users, users.length.toString()];
return users
}
function notifyUsers() {
// Retrieve all users now
const currentUsers = getUsers()
// Send a message to each user
currentUsers.forEach(user => sendMessage(user))
console.log('I have sent everyone a message')
}
function sendMessage(user) {
console.log(`Sending message to ${user}`)
}
// Start the application by looping every <whatever>
setInterval(() => notifyUsers(), 1000)