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The LoopThis is not a function error has to do with the LoopThis(); code in your switch. It is calling a function. In FiveLoop you set LoopThis to LoopFunction. So it only runs the function you give it. That is why this works: FiveLoop(TypeWrite);

Here, I'll show you a more or less correct proof of concept that doesn't do weird things. In this way I hope you can learn something more about JS and Sphere.

Code: (javascript) [Select]

function TextTyper()
{
    this.msg = "";
    this.loc = 0;
    this.wind = GetSystemWindowStyle();
    this.font = GetSystemFont();
    this.time = 0;
}

TextTyper.prototype.type = function(msg) {
    this.msg = msg;
    this.loc = 0;
    this.time = GetTime();
}

TextTyper.prototype.update = function() {
    this.wind.drawWindow(16, 16, 256, 128);
    this.font.drawTextBox(16, 16, 256, 128, 0, this.msg.substr(0, this.loc));
	
	if (this.time + 25 < GetTime()) {
		if (this.loc < this.msg.length) this.loc++;
		this.time = GetTime();
	}
}

var typer = new TextTyper();

function game()
{
    typer.type("Hello, how are you doing? This is a fine day, have fun!");
    SetRenderScript("typer.update();");
    MapEngine("test.rmp", 60);
}

Indeed in JS you may almost get by without switches; they are just a stylistic method of handling things that would take many if conditions, and perhaps faster to execute depending on the circumstance.

But what I don't understand is why, if I pass a function with arguments through FiveLoop, it errors. I know it only runs the function I give it, but why is such a limitation placed on the functions I can give it? Why can't I have TypeWrite be given a string in code ("TypeWrite(string)") and then do FiveLoop(TypeWrite("Hello, world!"));

I actually do know how switch cases work, I just had to hack it to get it to do what I wanted. Normally, yes, you pass a value to check into the switch, however, if you pass "true" into a switch, you can have complex cases that check multiple things at once

I told you my code was awful. I warned you. You were warned :p

Quote from: Mooch – on December 10, 2013, 05:05:22 pm

But what I don't understand is why, if I pass a function with arguments through FiveLoop, it errors. I know it only runs the function I give it, but why is such a limitation placed on the functions I can give it? Why can't I have TypeWrite be given a string in code ("TypeWrite(string)") and then do FiveLoop(TypeWrite("Hello, world!"));

Wait, what exactly are you trying to do here? If you are trying to use callbacks, you probably will want to use anonymous functions.

Code: [Select]

function DoThings(f){
  f();
}

//Let's say I want to draw some text...

DoThings(
  function(){
    GetSystemFont().drawText(16, 16, "Words!");
  }
);

//Or, I think this is exactly what you want...
FiveLoop(function(){TypeWriter("Hello, World!");});

That's a simple way to pass a function and associated arguments as a callback. It constructs a function inline, and gives that as an argument. Very useful for callbacks when you need variable numbers or action-specific arguments.

Quote from: mooch

I actually do know how switch cases work, I just had to hack it to get it to do what I wanted. Normally, yes, you pass a value to check into the switch, however, if you pass "true" into a switch, you can have complex cases that check multiple things at once

I don't agree with the switch stuff from a purely syntactical point of view: I'd rather use if statements, since that's exactly what you were wanting to do out of it.

And no, your switch does not work as you think it does since the only two values from a condition is either true or false, so only two things of that switch ever get executed, which two is beyond me, and why your code works is beyond me and I've been programming JS for near a decade now.

I'm not angry or anything, I'm just confused by the code that's all.

If you wanted a five-loop to do things over time, well, you can do something like this:

Code: (javascript) [Select]

function Looper(times, func)
{
    this.times = times;
    this.func = func;
}

Looper.prototype.update = function() {
    if (this.times > 0) {
        this.func();
        this.times--;
    }
}

Looper.prototype.isFinished = function() { return this.times == 0; }

var txtlen = text.length;
function DecrementText() {
    txtlen--;
}

var fiveloop = new Looper(5, Decrement);

function game() {
   SetRenderScript("fiveloop.update();");
   MapEngine("map.rmp", 60);
}

I know I'm writing code for you, but my intention is for you to try and learn from it. Really! Sometimes your first pass is good, but then once you see someone elses code you get better. I had to show you code since you are destroying your own knowledge of JS by using switches in unintended ways, and that might be an issue later on down the road.

So, OOP.

In JS all functions are objects.

Code: (javascript) [Select]

function MyObject(a_size) {
    this.size = a_size;
    this.weight = 20;
}

MyObject.prototype.print = function() {
    Abort("My size is: "+ this.size + ", and weight: " + this.weight + ".");
}

var obj1 = new MyObject(15);
obj1.print(); // says it has size 15, weight 20.

var obj2 = new MyObject(5);
obj2.print(); // says it has size 5, weight 20.

The 'this' pointer refers to the current object in scope. Most of the time it is the direct object you are working with. By using 'this' you can store variables into the object to persist them for use later on. This is good in RPG games since you have many stats you want to keep around, like player stats and enemy stats.

The 'prototype' keyword is uesd to attach a method or property onto the object at a more fundamental level. By using prototype to attach a function to an object you create a method - a function that does work with respect to the object it is attached to.

Notice in 'print' I used 'this'? That means I can recall the variable stored in the object and use it. Notice in the code above obj1 and obj2 print out different results? That's because the size property of each has changed.

This was useful in my typing demo to store the message and how far along it has typed out. You were doing this too, albeit in the global scope using global variables, which is not bad for first time (easily the easiest way to do it). But then you start having too many variables in the global scope which might be a bad thing later on. Object contain the variables in their own self, so two objects can have the same property name, but different values.

If you do this:

Code: (javascript) [Select]

function MyObject(a_size) {
    var size = a_size;
    this.weight = 20;
}

The size variables would be destroyed at the termination of the function. The 'this' value persists it within the object.

Quote from: Mooch – on December 10, 2013, 05:05:22 pm

I told you my code was awful. I warned you. You were warned :p

So close, but no cigar.  How you say that is "I warned you about code bro! I told you dog!"

...yeah, no, I couldn't resist. :p

Quote from: Radnen – on December 10, 2013, 05:36:12 pm

If you do this:

Code: (javascript) [Select]

function MyObject(a_size) {
    var size = a_size;
    this.weight = 20;
}

The size variables would be destroyed at the termination of the function. The 'this' value persists it within the object.

Might it sometimes (probably rarely if ever) be advantageous to have variables destroyed when a function is done running? Especially if working with older tech where resources are limited, it might sometimes be better to have them destroyed so they don't linger around, eating up RAM.