Skip to main content

javascript hoisting

Javascript hoisting:
In JavaScript, Hoisting is the default behavior of moving all the declarations at the top of the scope before code execution. Basically, it gives us an advantage that no matter where functions and variables are declared, they are moved to the top of their scope regardless of whether their scope is global or local

We can call as all the declaration variable going to top while executing the application.

Above image assigning x=1 and it is not declared, after creating the alert then declaring the variable.
Here it is not throwing any error while executing javascript declarations are going to top.
Here var x: is going to top then assigning x=1:
Code snippet:

// program to display value
var a = 6;

function greet() {
b = 'hi';
console.log(b); // hi
var b;
}

greet(); // hi
console.log(b);

Output :
Hi
Uncaught ReferenceError: b is not defined

Comments

Popular posts from this blog

Applications of Insulating Materials

All electrical systems require some kind of insulation to prevent short circuits and leaking currents. 3 forms of insulators: solid, liquid and gaseous Performance of these insulators depend on the temperature Classification according to their temperature rating. Impregnation: Letting the solid material absorb some liquid With the advent of new materials, the classification has been modified by International Electrotechnical Commission: The transformer insulation: (a) conductor or turn-to-turn insulation, (b) coil-to-coil insulation, (c) low voltage coil-to-earth insulation, (d) high voltage coil-to-low voltage coil insulation, and (e) high voltage coil-to-ground insulation. Transformer oil -- provides the required dielectric strength and insulation -- cools the transformer by circulating itself through the core and the coil structure. -- should be in the liquid state over the complete operating range of temperatures between -40°C and+50°C. -- gets o...

How to use My Eclipse in Java part4

Q) write a program to understand debugging? most commonly used shortcuts ----------------------------------------- Files / windows control --> save : ctrl+s --> save all : ctrl+shift+s --> maximise / minimise window : ctrl + m --> close a file in the window : ctrl + f4 / ctrl+w --> close all files : ctrl + shift + w --> how to change the file name : right click -> refactor -> rename -->How to change a variable name : select variable + right click on variable + refactor + rename + give new name + press enter. Code Editing --> format code : ctrl+shift+f --> organize imports : ctrl +shift + o --> single line comment OR un comment : ctrl+ / --> multi line comment : ctrl+shift+/ --> multi line un comment : ctrl + shift + \ -->delete line : Ctrl + D --> how to generate setters and getters : -> right click -> source -> generate getters and setters --> short form System.out.println : syso+ ctr...