How Operators work in Javascript

Before we dive deep even futher let’s get to know what is operators.

Operator is a special function that is written differently than a regular function, Generally operator take two parameters and return one result.

Lets say you want to create a variable

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const a = 5 + 4;

console.log(a);

I bet you can guess what the result is

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9;

Correct 9, obviously 5 + 4 is equal to 9, but there is a question you may ask, “How the Javascript do that?” or “How Javascript know that 5 + 4 is an addition?”.

Well, first the Javascript engine will see the + sign and add the numbers in between which is 5 and 4. The + sign is an operators and it’s actually a function, kinda like this:

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function +(num1, num2) {

  return // sum the two numbers

}

The function will run as soon as the Javascript see this 5 + 4 line of code, the different is instead calling the function normally like +(5, 4) the Javascript engine provide an ability to write a Infix notation.

Infix simply mean the function + sit between the two parametes. To get an idea how it work we will compare Prefix, Infix and Postfix notation.

Prefix Notation equal to +5 4 the + sign sit in the beginning \

Infix Notation equal to 5 + 4 the + sign sit in the middle \

Postfix Notation equal to 5 4+ the + sign sit in the end

You can see the Infix notation sit between the two parameters, but in the end it’s just a function and return a value.

In this case the + operator get called and return 5 and 4 added together.

The - operator work exactly the same for example:

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const a = 3 - 2;

console.log(a);

I think you can already guess the result, it’s 1 because - is an operator a minus sign. or you can do another one

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const a = 3 > 2;

console.log(a);

> the greater than is just a function, a special function, this operator work the same way except that this operator return a Boolean value.

Whenever you write +, -, <, > and all other operators out there that this is just a special types of function. The two parametes is being passed to the function and the function have a pre written code inside of it that Javascript engine provide for you and then it will return a value it could be a Number, Boolean etc.

So please keep in mind that operators is just a function.

Thank you for reading 🙇‍♂️.