10 Fundamentals, JavaScript Developer’s should know

1. Try …Catch:

try{
// code start to execute the whole code, unless it'll find any error
}
catch{
//if any error found in try , then catch is began to execute and execution doesnt blocked due to error. It gives the programmer the error message which helps the programmers to debug
}

2. Var Declarations and Hoisting:

3. Block-Level Declarations

4. Default Parameters Value in ES6

const add =(a=3, b=5) => {
return a + b;
}

add(4,2) // 6
add(4) // 9
add() // 8

5. Spread Operator

const pet = ['cat', 'dog', 'parrot'];

const wild = [...pet, 'wolf', 'lion'];
console.log(wild) // [ 'cat', 'dog', 'parrot', 'wolf', 'lion' ]
const pet = { animal-1: 'cat', animal-2: 'dog', animal-3: 'parrot'};
const wolf = {...pet, animal-4: 'wolf', animal-5: 'lion'};
console.log(wolf);
// {
animal1: 'cat',
animal2: 'dog',
animal3: 'parrot',
animal4: 'wolf',
animal5: 'lion'
}

6. Block level function

7. Arrow Function:

function add(a,b){
return a+b
}

8. Cross Browser Testing

9. Comments:

It is not necessary to tell “how code works” and “what it does”.

A Frontend Web Developer. Devoted to solving new problems and developing interactive web application