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TODAY I LEARNED

Javascript Hoisting

This means that variable and function declarations are physically moved to the beginning of the code and are allocated in memory during the compilation phase.

function welcomeTo(name) {
  console.log("Welcome to " + name);
}

welcomeTo("Magmalabs");
//returns welcome to magmalabs

As you can see hoisting allows you to use a function before declaring it in the code.

welcomeTo("Magmalabs");

function welcomeTo(name) {
  console.log("Welcome to " + name);
}
//returns welcome to magmalabs

And also allows you to use a function after declaring it in the code.

For variables, hoisting only applies to the declaration, not to their assignment. example:

We declare the variable name but we got an undefined

console.log(name); 
var name = magmalabs;
//return undefined

That’s because JavaScript only hoist the declaration

var name;

console.log(name); 
name = magmalabs;
//return undefined

To avoid these errors, it is very important to keep in mind that hoisting only applies to the declaration.

Learned by leyaim-jimenez on Sep 17, 2021

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