I'm working on a project that plays a game of rock paper scissors
the game works fine but i want to add something into it. a pointing system where it will add 1 each time a player win but i can't seem to make this work i've been trying to find workarounds for almost 2 day now but i can't seem to find any solution. The thing is the code works but after i log the function that adds 1 to a variable but after that it returns to it's original value which is 0.
const one = 1
function addone(test){
test += 1
}
addone(one)
console.log(one)
This print the original value like the function did not do anything to it. im so confused.
I see two problems in your code:
one is a const variable. That means that you can't modify its initial value.
test is a local variable inside your function, that means function won't modify the values of the variable that you pass as parameter (one).
There is an operator(++) that add a unit, I highly recommend you to use it instead of make a function:
var one = 1
one++;
console.log(one)
If you want to use a function you have to do like this:
var one = 1
function addone(test){
return test+1;
}
one = addone(one);
console.log(one)
In terms to store permanent data into a javascript variable, that's not possible. Variable are stored in RAM, that means that when you stop the program, al data of your program are wiped. Permanent store are made in database and other complex data structures.
If you want to play multiple games, you should consider to allow the players to play more games before the program finish.
thank you very much i never think that i could get more dumb so i cant manipulate it because it's just a copy of that variable that im inputing as parameter? so it means that the function did not touch the variable at all. I wish i could go back to my mother's womb.
and the const it's just a typo very sorry for this.
i did not know this website is very active i thought i would wait days just to get a response thank you very much and have a nice day
Related
I'll start with the exact nature of the problem and then give some background. I am trying to name a function -threadTimer- and give it a random unique identifier, such as 'threadTimer'+ID. A randomly generated ID would work fine. Then, I need to use setInterval on it, to make it fire repeatedly and therein lies my coding problem. I have tried every variation of new, function, function as an object and I just can't get my head around it. You'll notice that the function I have created is an object and perhaps this is where I'm going in circles.
OK, the background I mentioned. threadTimer is fired by a master timer co-ordinating several threads. That's why you'll see I have generated a 'global' object for reference elsewhere. similar HTML entities can fire threadTimer at the same time, hence my requirement to make each instance unique.
window['GlblThreadExe'+ID]=setInterval(function(){threadTimer(elid,parent,lft,top,diameter,point,bStyle,color,grp,startTime,size,ID,counter,div,divwth,divht,wthIncrement,htIncrement,lftStart,topStart,lftIncrement,topIncrement)},interval);
function threadTimer(elid,parent,lft,top,diameter,point,bStyle,color,grp,startTime,size,ID,counter,div,divwth,divht,wthIncrement,htIncrement,lftStart,topStart,lftIncrement,topIncrement){
// more code
}
In truth, I think its the volume of parameters that I'm passing that's confusing my syntax. Any help appreciated
Avoid polluting window
Generally instead of polluting the global namespace you can store your setInterval ids in some variable
let intervalIds = {}
intervalIds['GlblThreadExe'+ID] = setInterval(function()...)
If really necessary, then store intervalIds to window
window.intervalIds = intervalIds;
Wrap your anonymous function
When you create the "clock", do not call setInterval directly:
Here, createTimerWithId will return a function which calls threadTimer
Dirty id generation
Use a timestamp, and mix it with some random stuff. Or better use a UUID
setInterval(createTimerWithId(), 1000)
function createTimerWithId(){
let id = Date.now()+Math.random(); //no lib, oneliner. good enough to debug
return function(){//the same function you gave to setInterval in your example
threadTimer(id, ...)
}
}
We can do better
In 1. we generated an id on the fly and thus
your code is not testable (id will always change(well except if you mock Math and Date...)).
your id is ugly (a float...)
it will be hard to know from which setInterval you come from
instead, give it the ID.
function createTimerWithId(ID){
return function(){//the same function you gave to setInterval in your example
threadTimer(ID, ...)
}
}
window['..'+ID] = setInterval(createTimerWithId(ID));
shorter version being
window['..'+ID] = setInterval((id=>{
return function(){
threadTimer(id, ...)
}
})(ID),1000);
I'm really stuck on this javascript question!
So I'm making a web page that will be completely animated (so it can be used for display for example in a television). That animation will be configurable by the user (stored in a database).
Right now, I've already made the code to store the configuration and to get the configuration (I do an AJAX call and save the configuration in an array of json objects) and everything is as it should be.
The problem is in the animation in which I go through the array and use setTimeout function to create animations. To iterate through the array I rotate it
(I use array.push(array.shift()) according to the answer here).
The first time the intervalmaster function is used, everything goes according to plan, but when the function is called again I need to rotate the array once more (because of the last animation) and the array just doesn't rotate!
Bellow I've left a portion of the code that I'm using that reproduces the problem I'm getting. I've also added the array jsonanima with some possible values (In reality the array is probably much bigger and with higher values).
I really don't understand what is happening, I've also considered that this could be a problem of the multiple setTimeout functions because I've read somewhere (couldn't find the link, sorry!) that is not really advised to use multiple setTimeout.
If that's the case is there any other way to do this?
Thank you in advance!
EDIT: Thanks to the comment from mplungjan I've realized that if change the console.log(jsonanimate) to console.log(JSON.stringfy(jsonanima)) it outputs the correct values (the json array rotated). This got me even more confused! Why do I need to JSON.stringfy to get the array in the correct order?!
Anyway, can't test this with the full code now as I'm not in the office, tomorrow I'll give more feedback. Thank you mplungjan.
EDIT2: Finally solved my problem! So the thing was the call to the function recursivegroup (recursivegroup(0);), this call was made before I rotated the array, so when restarting the animation the array would still have the incorrect values and every sub-sequential value was wrong.
A special thanks to mplungjan and trincot for the comments that helped me debug this problem.
Bellow I leave the code corrected so anybody with the same problem can check it out.
jsonanima=[{"VD":5,"A":10,"diff":0.25},{"L":7,"IE":8,"diff":0.25}];
function intervalmaster(flag){
function recursivegroup(index)
{
if(index==0)
{
//animateeach(jsonanima,0);
}
setTimeout(function(){
//HERE IT WORKS
jsonanima.push(jsonanima.shift());
console.log(JSON.stringify(jsonanima));
//animateeach(jsonanima,0);
//removed the if statement, since it was irrelevant as mplungjan noted
recursivegroup(index+1);
},(jsonanima[0]['diff'])*60*1000);
}
//Changed this
//recursivegroup(0);
var mastertime=0;
for(var key in jsonanima)
{
mastertime+=(jsonanima[key]['diff']);
}
console.log(mastertime,flag);
console.log(JSON.stringify(jsonanima));
if(flag==true)
{
jsonanima.push(jsonanima.shift());
console.log(JSON.stringify(jsonanima));
}
//changed to here
recursivegroup(0);
masterinterval=setTimeout(function(){intervalmaster(true)},mastertime*60*1000);
}
intervalmaster(false);
So I'm basically trying to implement an online trading card game in php and (maybe minimal) javascript, and so far I have a GUI set up in php, a database with the required tables (so far) to hold the decks, fields, and other various data. I've got it to the point where i have a function that initializes the fields for both players and populates their fields and hands with cards from their deck. I also got it to the point where a player on another computer or device can take the room number of the game and join the game so the see the exact initialized field.
my next objective was to be able to set up the turn logic, and allow the screen to update for one player while the other is making plays during their turn. My problem is I'm not sure what the minimum viable solution will be for this, because I have long intricate functions that display the current field based off of values that come from a field table. So my ideal logic is set up like this:
//find game form
//host game form
//if host is set (post){
//call insert field function (a long function that creates a table for the current game being played and initializes the field and hand with random cards from the deck table)
//link game to host for future field printing
// populate host function (a function that prints a table of every card on the field with the most up to date variables to represent each spot)
}
//if find is set (post){
//call insert field function
//link game to host for future field printing
//a button form to start the game which begins by calling heads or tails
// populate find function (same as host but for find player side)
}
//if start game is set (post){
// do game logic such as coin flip which will be notified to opponent in a message field in the game table upon the refresh
}
I was wrapping the populate host function in a refreshable div like this:
print "<div><meta http-equiv='refresh' content='5' />"; //host populate just disapears
populatehost($roomnumber); //populates self and opponents in hosts perspsective
print "</div>";
so that the function would be called every 5 seconds or so, but this just causes the field to disappear after 5 seconds. So...
Why is it disappearing?
How can i get it to refresh the page and just display one instance of the field using the populate field function?
Is this approach viable? if not, what's the easiest approach I could take and how?
I also tried a solution where the function was called every 5 seconds and gotten rid of, but i'm not sure if I was doing it right, the PHP manual didn't explain it very clearly, and after lots of trial and error i think i crashed my server. It was something like this:
//loop
ob_start();
populatehost($_SESSION['gamenumber']);
sleep(5);
ob_end_clean();
I kept playing around with that logic but it either printed infinitely, didn't print at all, or crashed my server. I'm afraid to play around even more for fear of crashing the server again. Maybe someone can explain the correct way to do it or why it is not viable if it isn't?
I'm sorry if these are dumb questions, I've spent days and days researching approaches to this problem, I wasn't sure if I could implement it using javascript or ajax along with my field printing function, I tried some and they weren't working, and I'm not sure if it's because my approach is viable or not.
You can take javascript or Ajax help for div you can assign id to the div and call id in javascript:
jQuery(function () {
var $els = $('div[id^=quote]'),
i = 0,
len = $els.length;
$els.slice(1).hide();
setInterval(function () {
$els.eq(i).fadeOut(function () {
i = (i + 1) % len
$els.eq(i).fadeIn();
})
}, 2500)
})
check this fiddle:
http://jsfiddle.net/arunpjohny/asTBL/
Thanks
I am currently learning JavaScript and I am wondering what is the role of the variables (var).
In the example bellow, on the last two lines we first define a variable "monCompte" in which we call "john.demandeCaissier(1234)". Then we use console.log(monCompte) to print the result on the screen. What I don't understand is why do we first need to define the variable "monCompte" to call "john.demandeCaissier(1234)". Why can't we just do something such as:
console.log(john.demandeCaissier(1234));
Example
function Personne(prenom,nom,age) {
this.prenom = prenom;
this.nom = nom;
this.age = age;
var compteEnBanque = 7500;
this.demandeCaissier = function(mdp) {
if (mdp == 1234) {
return compteEnBanque;
}
else {
return "Mot de passe faux.";
}
};
}
var john = new Personne('John','Smith',30);
var monCompte = john.demandeCaissier(1234);
console.log(monCompte);
Thank you for you answers.
Yes, you can inline your function call and avoid the need for a variable. However, if an error occurs on that line, it becomes harder to debug:
var monCompte = john.demandeCaissier(1234);
console.log(monCompte);
vs
console.log(john.demandeCaissier(1234));
in the second example, there are several different modes of failure that would not be apparent in a debugging session. When split over two lines, some of those failures become easier to track down.
Second, if you wanted to reuse the value returned by john.demandeCaissier(1234) (the author might have shown this), then a variable becomes very useful indeed.
In my opinion, it's a worthy pursuit to perform only a single operation per line. Fluent-style advocates might disagree here, but it really does make debugging considerably easier.
You could definitely do that, but in more complex programs you will need to store variables for several reasons:
Shortening Long Expressions
Imagine if you saw this code somewhere:
console.log((parseInt(parseFloat(lev_c + end_lev_c)) - parseInt(parseFloat(lev_c + start_lev_c)) + 1));
BTW I got that from here
Wouldn't it be so much simpler just to split that expression up into different variables?
Storing Data
Let's say that you take some input from the user. How would you refer to it later? You cannot use a literal value because you don't know what the user entered, so do you just call the input function again? No, because then it would take the input a second time. What you do is you store the input from the user in a variable and refer to it later on in the code. That way, you can retrieve the value at any time in the program.
If you are a beginner, you might not see any use for variables, but when you start writing larger programs you will start to use variables literally in almost every line of code.
Variables exist to store data. They're useful because instead of invoking an operation over and over again, which is criminally inefficient, they allow you to invoke an operation once, and then use that result where necessary.
And that's for all languages, not just JavaScript.
Variables are structures that store some value (or values). They're only that and you could probably do all your code (or the majority of it) without them.
They help you organize and add some readability to your code. Example:
alert(sumNumbers(askNumber()+askNumber()));
takes a lot more effort to read/understand then this:
var firstNumber = askNumber();
var secondNumber = askNumber();
var total = sumNumbers(firstNumber + secondNumber);
alert(total);
Sure it's longer but it's more readable. Of course you don't have to use var for everything, in this case I could just hide the total.
Another common use for variables is "caching" a value.
If you had a function that sums like 1 million values, if you keep calling it for everything, your code would always have to do all that hard work.
On the other hand, if you store it on a variable the first time you call it, every other time you need that value again, you could just use the variable, since its a "copy" of that calculation and the result is already there.
So I am making a hacking type game coded with HTML and JavaScript, and I made a Store.html file for my store to purchase upgrades for your hacking system. I have several variables that I want to view and change from a different file than the one that I originally have it inside of.
Variable 1
var tutorialDone = false
Variable 2
var jobBoolean
Variable 3
var bitCoins = 30
var currentBit = bitCoins
I want this to be false because when the tutorial mission is finished, then I want to change the jobBoolean variable to "true" because when the tutorial mission is completed, then I want a new list of missions/jobs to show up on thee screen. The first mission is a seperate page. At the end of the mission when it is completed, then "tutorialDone" I want to be equal to "true", so that when I am back at the homepage, I can change the jobBoolean to true. Because the "tutorialDone" variable is dependent on the "jobBoolean" variable. When "tutorialDone" equals "true" so does "jobBoolean". I don't know how to make "tutorialDone" change along with the "jobBoolean".
I have for the third variable, there is two. That is because they are similar. I have a function inside the "Store.html" document that when an item is purchased, it grabs a variable which in this case is "currentBit". "currentBit" is equal to "bitCoins" because I thought that if I made a new variable, "currentBit", then set it equal to "bitCoins", it would connect with "bitCoins" from a seperate file. This was my only "solution" I could think of, but it doesn't work.
Also, as a bonus answer for you guys, how can I make an "if" statement in JavaScript, and then have it check if the variable I give it is equal to something, and if it is, run some code. Because whenever I try it, the function the if statement is in, it will run through the if part of the statement no matter if the statement is true or false.
Sorry if this question doesn't make much sense. This is just the first big problem I have encountered with JavaScript, that I couldn't fix myself.