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Lanalen
Lanalen

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What I learnt today: Function

Declaration vs Expression

Declaration

function myFunction() {
    console.log("hi");
}
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Expression

const a = function() {console.log("hi")};
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The Function Constructor : Function()

usage

const a = new Function("x", "y", "return x + y");
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also possible without new keyword

const a = Fuction("x", "y", "return x + y");
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Function Hoisting

What is it? To call a function before declaring it.

myFunction();

function myFunction() {
    console.log("hi");
}
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Parameter vs Argument

function myFunction(name) {
     console.log("Hi", name);
}

myFunction("Lena");
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name is a parameter.
"Lena" is an argument.


Self-Invoking Function

What is meant by "self-invoking"? You don't need to call the function.
How to use? Put a function inside parentheses.

(function () {
     console.log("hi");
})();
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