JavaScript level Up step 10 points

1. Primitive Values​ is six types.

numbers, Boolean, String, Biglnt, symbol

2. object and function is not null . object and function are values. object and function result show browser inspect colsole.log(). then show object and function values.

3. javascript cheacking string and numbers and object ,

console.log(takeOf(4)); // number

console.log(takeOf(“rakibul”)); // string

console.log(takeOf(undefined)); // undefined

4. Javascript cheaking object and function rules

console.log(typeof({})); // object

console.log(typeof([])); // object
console.log(typeof(a => a+ 4)); // function

5. javaScript one line true false,

= object true ? false

6. JavaScript error handling try catch rules try {//code}

7. var all time data decaler , let all time change data values. const one time data data antry …before change data then santeyx error ,

8. Labelled Block Statement

LabelIdentifier: {
  StatementList
}

Labelidentifier target is break.

9. Arrow function expressions exmaple : -

const name= [
‘rakibul’,
‘monika’,
‘banecha ’,
‘wasife’
];

console.log(name.map(name => name.length));
// expected output: Array [8, 6, 7, 9]

10. Spread syntax

function sum(a, b, c) {
return a+ b+ c;
}

const numbers = [1, 2, 3];

console.log(sum(…numbers));
// expected output: 6

console.log(sum.apply(null, numbers));
// expected output: