Usage of reference parameters and how it can be used in functions - JavaScript

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Can you please let me know with simple examples on:

Usage of reference parameters and how it can be used in functions - JavaScript

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milani_lucieAsked:
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Kiran SonawaneConnect With a Mentor Project LeadCommented:
When passing in a primitive type variable like a string or a number, the value is passed in by value. This means that any changes to that variable while in the function are completely separate from anything that happens outside the function. Let’s take a look at the following example:
function myfunction(x)
{
      // x is equal to 4
      x = 5;
      // x is now equal to 5
}

var x = 4;
alert(x); // x is equal to 4
myfunction(x); 
alert(x); // x is still equal to 4

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Passing in an object, however, passes it in by reference. In this case, any property of that object is accessible within the function. Let’s take a look at another example:

function myobject()
{
	this.value = 5;
}
var o = new myobject();
alert(o.value); // o.value = 5
function objectchanger(fnc)
{
	fnc.value = 6;
}
objectchanger(o);
alert(o.value); // o.value is now equal to 6

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0
 
Gurvinder Pal SinghCommented:
like this

function a()
{
   alert("1");
}

//settimeout will use the function reference to call it

setTimeout(a, 1000); //a method will be called after a second
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