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why am i not able to import the class to another js file

class hello{
var1;
var2;
constructor(var1, var2){
this.var1 = var1;
this.var2 = var2;
}
getVar(){
console.log(this.var1);
console.log(this.var2);
}
}
class h1 extends hello{
var3 ;
constructor(var1, var2,var3)
{
super(var1,var2);
this.var3 = var3;
}
getAll(){
console.log(this.var1);
console.log(this.var2);
console.log(this.var3);
}
}
export {h1};
export {hello};
This is a module that I want to import from another file
This is the code of another file
import {h1,hello} from './temp'
let a = new h1("likith","ramu","asha");
a.getAll();
let b = new hello("raju","rahil");
b.getVar();
And this is the error that I'm getting for this code Please solve this problem
**
(node:14232) Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
(Use node --trace-warnings ... to show where the warning was created)
c:\Full stack dev Code\react.js\temp1.js:1
import {h1,hello} from './temp'
^^^^^^
SyntaxError: Cannot use import statement outside a module
at Object.compileFunction (node:vm:352:18)
at wrapSafe (node:internal/modules/cjs/loader:1033:15)
at Module._compile (node:internal/modules/cjs/loader:1069:27)
at Object.Module._extensions..js (node:internal/modules/cjs/loader:1159:10)
at Module.load (node:internal/modules/cjs/loader:981:32)
at Function.Module._load (node:internal/modules/cjs/loader:822:12)
at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:77:12)
at node:internal/main/run_main_module:17:47
[Done] exited with code=1 in 0.125 seconds
**

Since you are trying to import a module it will be better if you try exporting your classes as a module as well, like this, module.exports = { h1, hello };
and then you can import it in your other file like this, const { h1, hello } = require("./temp");.
Hope this solves your problem

Can not import custom created class in JS

I am importing the following class which I created like so
import Select from './operations/select.js'
select.js
export default class Select{
constructor(db){
this.db = db
}
allGenres(){
return new Promise((res,rej)=>{
this.db.all(`SELECT * FROM genre`,(err,rows)=>{
if(err) res(err)
else res(rows)
})
})
}
}
I wish to do something like
return await new Select(db).allGenres()
But I am getting the following
(node:38769) Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
(Use `node --trace-warnings ...` to show where the warning was created)
/home/lucky/workspace/web/vibe-backend/index.js:2
import Select from './operations/select.js'
^^^^^^
SyntaxError: Cannot use import statement outside a module
at wrapSafe (node:internal/modules/cjs/loader:1018:16)
at Module._compile (node:internal/modules/cjs/loader:1066:27)
at Object.Module._extensions..js (node:internal/modules/cjs/loader:1131:10)
at Module.load (node:internal/modules/cjs/loader:967:32)
at Function.Module._load (node:internal/modules/cjs/loader:807:14)
at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:76:12)
at node:internal/main/run_main_module:17:47
thank you for yout time.

Change to:
const Select = require('./operations/select.js');

function rest parameters throw error

running:
$> node restparamstest.js
where:
restparamstest.js
var addTestNotification = function(x, ...theArgs) {
theArgs.forEach(function (post) {
console.log(post);
});
};
addTestNotification(1, 2, 4);
throws:
(function (exports, require, module, __filename, __dirname) { var addTestNotification = function(x, ...theArgs) {
^^^
SyntaxError: Unexpected token ...
at exports.runInThisContext (vm.js:53:16)
at Module._compile (module.js:373:25)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Function.Module.runMain (module.js:441:10)
at startup (node.js:139:18)
at node.js:968:3
on node version:
console.log(process.versions);
{ http_parser: '2.5.2',
node: '4.4.7',
v8: '4.5.103.36',
any ideas? Thanks!

Rest parameters are fully supported only since node 6.31. If you want to use them with earlier versions of node, you should use the --harmony flag.
You can see ES2015 support by node version here.

Give it a try like this
node --harmony restparamstest.js

JavaScript Exporting a class definition [duplicate]

This question already has answers here:
Destructuring in Node.JS
(3 answers)
Closed 7 years ago.
Can I export class definition in JavaScript? For example,
in file "HelloWorld.js":
'use strict';
class HelloWorld {
constructor(msg = 'Hello World~') {
this.message = msg;
}
sayHi() {
console.log(this.message);
}
}
module.exports = HelloWorld;
Then in "index.js"
'use strict';
var HelloWorld = require('HelloWorld');
var myObj = new HelloWorld;
myObj.sayHi();
if I do "node index.js", then I got the error below:
constructor(msg = 'Hello World~') {
^
SyntaxError: Unexpected token =
at exports.runInThisContext (vm.js:53:16)
at Module._compile (module.js:387:25)
at Object.Module._extensions..js (module.js:422:10)
at Module.load (module.js:357:32)
at Function.Module._load (module.js:314:12)
at Module.require (module.js:367:17)
at require (internal/module.js:16:19)
at Object.<anonymous> (/data/users/soltiho/fbsource/fbcode/video_templates/test_env/index.js:3:18)
at Module._compile (module.js:413:34)
at Object.Module._extensions..js (module.js:422:10)
my node is v5.5.0

Node doesn't support destructuring (yet), and using destructuring would be wrong anyways. There is nothing special about importing/exporting a class. Import it like any other module:
var myValue = require('myVModule');

Error: cannot find module when testing with mocha

I'm using babeljs to write an RPG engine library. I have two files:
dice.js
import assert from 'assert';
import Random from 'random-js';
export default class Dice {
constructor(maxNumber) {
assert(typeof(maxNumber) === "number", "maxNumber must be a number");
this._mt = Random.engines.mt19937();
this.minNumber = 1;
this.maxNumber = maxNumber;
}
makeThrow() {
this._mt.autoSeed();
return Random.integer(this.minNumber, this.maxNumber)(this._mt);
}
}
throwManager.js
import assert from 'assert';
import Dice from 'dice';
export default class ThrowManager {
constructor(settings) {
assert(settings.hasOwnProperty("numberOfDices"), "must set 'numberOfDices'");
assert(settings.hasOwnProperty("maxNumberInDice"), "must set 'maxNumberInDice'");
assert(settings.maxNumberInDice <= 1, "must have at least 1 dice");
this.settings = settings;
}
execute() {
var throwResults = [];
for (var d = 1; d <= this.settings.numberOfDices; d++) {
var dice = new Dice(this.settings.maxNumberInDice);
throwResults.push(dice.makeThrow());
};
return throwResults;
}
}
When I test them with mocha, I do these imports:
tests.js
var assert = require('assert');
var Amzhen = require('../Amzhen.js');
var random = require('random-js');
//tests here...
Yet when I run the tests, I get this:
Error: Cannot find module 'dice'
at Function.Module._resolveFilename (module.js:338:15)
at Function.Module._load (module.js:280:25)
at Module.require (module.js:364:17)
at require (module.js:380:17)
at Object.<anonymous> (/home/joel/Amzhen.js/Amzhen.js:47:28)
at Module._compile (module.js:456:26)
at Object.Module._extensions..js (module.js:474:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Module.require (module.js:364:17)
at require (module.js:380:17)
at Object.<anonymous> (/home/joel/Amzhen.js/test/tests.js:2:14)
Any ideas why the dice module isn't being found?
I'm compiling the code with babel src --out-file Amzhen.js && mocha

You should use:
import Dice from './dice';
'dice' is not the name of a published, installed Node.js module, but a local file, so you should use ./dice with an appropriate path.
See also Module not found error in node.js