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Can not use class in a function as a parameter (JScript)

I am trying to do a small JavaScript Lab. In the lab, first I created an Animal object :
function Animal(species, nature) {
this.species = species;
this.nature = nature;
var preys = new Array();
Animal.prototype.getSpecies = function() {
return species;
}
Animal.prototype.getNature = function() {
return nature;
}
Animal.prototype.getPreys = function () {
return preys;
}
Animal.prototype.setNature = function (newNature) {
nature = newNature;
}
Animal.prototype.setSpecies = function (newSpecies) {
species = newSpecies;
}
Animal.prototype.setPrey = function (newPreys) {
preys = newPreys;
}
}
Then, I created a World object which will basically store a number of animal object and separate them according to their nature.
/// <reference path="Animal.js" />
function World() {
var animals = new Array();
animals.push(new Animal("Wolf", "Carnivore"));
animals.push(new Animal("Crocodile", "Carnivore"));
animals.push(new Animal("Sheep", "Omnivore"));
World.prototype.getOmnivores = function () {
return animals.filter(getOmnivores());
}
function getOmnivores(animal) {
}
}
In my getOmnivors function, I can not use the Animal class as a variable. It is a little bit complicated for me cause I am new in JavaScript and regardless of their types we are using var keyword (Or not using in some places such as parameters in functions).
What did I do wrong and how can I fix it? I could not reach the Animal class in my private function getOmnivores. I think program does not understand that it is the class called Animal
I hope I explained well. Have a nice day!
EDIT
Error picture :

Animal is the Class name, you don't need it there. When using filter each element of the array is automatically passed on to the callback function as the first parameter of that function.
Since each element of the array is an instance of the class Animal you can use it straight away.
Also, the syntax {ClassName}.Prototype.{functionName} should not be used within that same Class, because by the time the interpreter reaches that line the Animal Class has not yet been defined. That syntax is used on already existing and defined classes. Use this.{functionName} instead.
function Animal(species, nature) {
this.species = species;
this.nature = nature;
this.preys = new Array();
this.getSpecies = function() {
return this.species;
}
this.getNature = function() {
return this.nature;
}
this.getPreys = function () {
return this.preys;
}
this.setNature = function (newNature) {
this.nature = newNature;
}
this.setSpecies = function (newSpecies) {
this.species = newSpecies;
}
this.setPrey = function (newPreys) {
this.preys = newPreys;
}
}
function World() {
var animals = new Array();
animals.push(new Animal("Wolf", "Carnivore"));
animals.push(new Animal("Crocodile", "Carnivore"));
animals.push(new Animal("Sheep", "Omnivore"));
this.getOmnivores = function () {
return animals.filter(this.filterOmnivores);
}
this.filterOmnivores= function(animal) {
return animal.getNature()=='Omnivore';
}
}
myworld = new World();
console.log(myworld.getOmnivores());
A working fiddle at https://jsfiddle.net/47dyg1q9/

The filter method takes a function as a paramter.
You must provide the function but in your code you are instantly calling the function:
World.prototype.getOmnivores = function () {
return animals.filter(getOmnivores());
}
Remove the parentheses to provide just the function without calling it, or insert an anonymous function:
World.prototype.getOmnivores = function () {
return animals.filter(getOmnivores);
}
// or
World.prototype.getOmnivores = function () {
return animals.filter(function (animal) {
return animal.nature === "omnivore";
});
}

You need to pass the function as an argument, not what it returns.
return animals.filter(isOmnivore);
And isOmnivore becomes
function isOmnivore(animal) {
animal.nature == 'Omnivore';
}

break large public javascript functions into smaller private functions

I have JavaScript class which have huge functions which are very difficult to maintain.
The 2 public functions are called at start and then on click. I want to create private functions inside these public functions say break into into some private functions scope to these public methods.
var searchResultView;
var SearchResultView = function () {
me = this;
this.init = function () {
// huge code
}
this.Search = function () {
// huge code
}
}
jQuery(function () {
searchResultView = new SearchResultView();
searchResultView.init();
searchResultView.Search();
}
What will best way to achieve this. I tried to use below approach but i think this nested function will not work well.
var searchResultView;
function searchResultView() {
me = this;
this.init = function () {
var declareControls = function () {}
var addEvents = function () {}
var fillControls = function () {}
declareControls();
addEvents();
fillControls();
}
this.Search = function () {
var validateAndCreateCriteria = function () {
if (!validateAandGetLocation()) {
alert("invalid location");
return false;
}
if (!validateAandGetCategory()) {
alert("choose search type");
return false;
}
var validateAandGetLocation = function () {}
var validateAandGetCategory = function () {}
}
validateAndCreateCriteria();
}
}
jQuery(function () {
searchResultView = new searchResultView();
searchResultView.init();
});

If I understood correctly, you should have the functions something like this:
var foo = (function() {
var privateBar = function() { // private function
},
privatefooBar = function() { // private function
};
return {
publicFoo : function() { //public function
/* use privateBar and privatefooBar functions here */
}
};
})();
Later you can access publicFoo function by using
foo.publicFoo();
But you can't access the inside functions which are privateBar() and privatefooBar() directly because they are private functions.
Updated Fiddle

Breaking up the function is easy:
function f(..) {
// many lines here
return ret_f;
}
if equivalent to
function f {
function f1(..) {
// not so many lines here
}
function f2(..) {
// not so many lines here
}
var ret_f1 = f1(..);
var ret_f2 = f2(..);
// calculate ret_f from ret_f1 and ret_f2
return ret_f;
}
or if you prefer this style using anonymous functions
function f {
var f1 = function(..) {
// not so many lines here
};
var f2 = function(..) {
// not so many lines here
};
var ret_f1 = f1(..);
var ret_f2 = f2(..);
// calculate ret_f from ret_f1 and ret_f2
return ret_f;
}
I fear however your real question is specific to your existing code and is about what useful smaller functions to extract there and how to combine them.
For this one would need to have your full code and understand it. That might be a bit much for this QA format.

call javascript function after another

Can you please help answering this. Please not the contraints.
var myLib = {
var callback_one = function (result_from_web_service) {
console.log('callback_one');
};
var callback_one = function (result_from_web_service) {
console.log('callback_two');
};
var init = function () {
console.log('initializing...');
async_call_one(callback_one);
async_call_two(callback_two);
};
var doStuff = function () {
console.log('doStuff is called');
};
};
// User of my library
myLib.init();
myLib.doStuff();
// output
initializing...
doStuff is called
callback_one
callback_two
// What i need:
initializing...
callback_one
callback_two
doStuff is called
Constraint:
calling myLib.init shall not end up calling myLib.doStuff. i.e. myLib.init should be independent of myLib.doStuff
myLib.doStuff() should be called after myLib.init() and its callbacks are returned.
Thanks,

//You must change your API so init is async
//There is no way to have it wait until all initialization is done before it retuns
var init = function (initDone) {
console.log('initializing...');
var n = 0;
function serviceDone(){
n++;
if(n >= 2){ initDone() }
}
async_call_one(function(x){ callback_one(x); serviceDone() });
async_call_two(function(x){ callback_two(x); serviceDone() });
};
// User of my library
myLib.init(function(){
myLib.doStuff();
})
The way I parallelized those calls is very ad-hoc s not the most maintainable (there I need to keep the calls to serviceDone and the value of N in sync).. In the long run I would recommend using one of the many JS async programming libs out there.

hugomg has a good answer.
Yet I think it is really specific and could benefit a sort of workflow implementation, like this (approximately...):
function void() {}
var myLib = {
var g_flow = [];
g_flow[this.init] = [];
g_flow[this.init]["whendone"] = this.callback_one;
g_flow[this.init]["done"] = false;
g_flow[this.callback_one] = [];
g_flow[this.callback_one]["whendone"] = this.callback_two;
g_flow[this.callback_one]["done"] = false;
g_flow[this.callback_two] = [];
g_flow[this.callback_two]["whendone"] = this.doStuff;
g_flow[this.callback_two]["done"] = false;
g_flow[this.doStuff] = [];
g_flow[this.doStuff]["whendone"] = void;
g_flow[this.doStuff]["done"] = false;
var callback_one = function (result_from_web_service) {
console.log('callback_one');
};
var callback_one = function (result_from_web_service) {
console.log('callback_two');
};
var init = function () {
console.log('initializing...');
};
var doStuff = function () {
console.log('doStuff is called');
};
var flow_onward(hwnd) {
async_call(function(){ hwnd(); myLib.flow_onward(g_flow[hwnd]["whendone"]); });
}
flow_onward(this.init);
};
// User of my library
myLib.init();
myLib.doStuff();
Doing this way you can ensure the sequentiality and expand the numbers of callback as much as you want.
ps: this code has not been tested

jsMockito: How to run callback sended to mock?

I am learning how to use jsMockito to write perfect code. So, could you give me any idea on how to run callback which is provided to service?
Here is my class:
function MyClass(service) {
this.service = service;
}
MyClass.prototype.doSomething = function() {
this.service.doIt(function() {
console.log("How to run this function while running tests?");
})
}
And here is my test:
var MyClassTest = TestCase("MyClassTest");
MyClassTest.prototype.testMyClass = function() {
this.service = mock(Service);
this.myClass = new MyClass(this.service);
this.myClass.doSomething();
}
So, I need to see the log message:
"How to run this function while running tests?"
Any ideas are welcome.

Finally I have found the solution.
We need to create doItCallback:
function MyClass(service) {
this.service = service;
}
MyClass.prototype.doItCallback = function() {
console.log("How to run this function while running tests?");
}
MyClass.prototype.doSomething = function() {
this.service.doIt(this.doItCallback);
}
Also we need to update the mock:
var MyClassTest = TestCase("MyClassTest");
MyClassTest.prototype.testMyClass = function() {
this.service = mock(Service);
this.myClass = new MyClass(this.service);
var myClass = this.myClass;
when(this.service).doIt().then(function() {
myClass.doItCallback();
});
this.myClass.doSomething();
}

JavaScript: Accessing Nested Objects

The code looks like this
function Scripts() {this.FindById = function (id) {
this.FindById.constructor.prototype.value = function () {
return document.getElementById(id).value;
}}}
var Control = new Scripts();
Now when i say Control.FindById("T1").value(). I am not able to get the textInput("T1")'s value.

It seems that your code is a bit more complicated then it should be ;-)
Personally I would write it this way (not tested):
function Scripts() {
this.findById = function(id) {
var el = document.getElementById(id);
return {
value: function() {
return el.value;
}
}
}
}
The findById() now closes over a node and returns an interface that can return its value.
Also, your idea sounds a lot like Singleton, so you wouldn't even need the extra Scripts constructor:
var Control = {
findById: function(id) {
var el = document.getElementById(id);
return {
value: function() {
return el.value;
}
}
}
}
Working example: http://jsfiddle.net/YYkD7/

Try this:
function Scripts() {this.FindById = function (id) {
this.FindById.constructor.prototype.value = function () {
return document.getElementById(id).value
}}}
You didn't close the last "}" :-)