why array.map returns undefined

ByAnurag batra October 13, 2022October 23, 2022

let test = [ {name:'test',lastname:'kumar',age:30},
             {name:'test',lastname:'kumar',age:30},
             {name:'test3',lastname:'kumar',age:47},
             {name:'test',lastname:'kumar',age:28},
             {name:'test4',lastname:'kumar',age:30},
             {name:'test',lastname:'kumar',age:29}]

let result1 = test.filter(element => 
              { 
                 if (element.age === 30) 
                 {
                    return element;
                 }
              }).map(({lastname})=>lastname)
console.log(result1);
output : ['kumar','kumar','kumar']

Here is what the above code is Doing:
1. First, we are filtering the array based on the age.
2. Then, we are mapping the lastname of the filtered array.

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ByAnurag batra October 9, 2022September 6, 2022

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Target type ieee.std_logic_1164.STD_LOGIC_VECTOR in variable assignment is different from expression type ieee.std_logic_1164.STD_ULOGIC.

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Target type ieee.std_logic_1164.STD_LOGIC_VECTOR in variable assignment is different from expression type ieee.std_logic_1164.STD_ULOGIC.

ByAnurag batra September 20, 2022September 6, 2022

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ByAnurag batra October 17, 2022September 6, 2022

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simple callback pattern

ByAnurag batra October 18, 2022September 6, 2022

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send data to user node

ByAnurag batra October 9, 2022September 6, 2022

var http = require(‘http’); var data = “data to send to client”; var server = http.createServer(function (request, response) { response.writeHead(200, {“Content-Type”: “text/plain”}); response.write(data); // You Can Call Response.write Infinite Times BEFORE response.end response.end(“Hello World\n”); }).listen(8080); Here is what the above code is Doing: 1. We are creating a server using http.createServer() method. 2. We are…

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