constructor for class is undefined after require in module-CodePudding

I'm trying to import a class in node so I can make instances of it in my main function but when trying to do so I get the error Epicenter is not a constructor I have tried using export before my class and tried adding "type":"module" to my package.json but nothing seems to make a difference, I've tried using import as well but this doesn't resolve it either :(

my node version is 12.17.0, hoping someone will have some ideas, any insight is appreciated

here is my main module

const Epicenter = require("./EpicenterClass.js");


// makes a board where nodes are assigned randomly to slots 

const makeboard = (nodes, randomLimit) =>{
var map = [[]];
var nodeCount = 0;
map.length = Math.floor(Math.random(10) randomLimit);

console.log('making board',map,nodeCount,map.length)
for (const xloc of map) {
    Math.floor(Math.random(10) 1) > xloc && nodeCount < nodes ? map[xloc] = new Epicenter(1,2,3,4) 
    :
     map[xloc] = '';
    nodeCount  

    for (const yloc of map[xloc]) {
    Math.floor(Math.random(10) 1) > yloc && nodeCount < nodes ? map[yloc] = new Epicenter(1,2,3,4) 
    :
     map[yloc] = '';
    nodeCount  
      }     
  }

console.log(`${nodes} nodes generated, map generated: ${map}`)
}

makeboard(10, 2)

and here is my epicenter class

// adds an epicenter for an earthquake which can be placed on the board
   class Epicenter {
    constructor(lat, long, magnitude, width) {
      this.lat = lat;
      this.long = long;
      this.magnitude = magnitude;
      this.width = width;
    }

    shiftMagnitude(){
      this.magnitude = Math.floor(Math.random(10) this.magnitude);
      console.log('Magnitude of epicenter has changed')
    }
  }

for reference also here is my package.json

{
  "name": "edge_testing_lab",
  "version": "1.0.0",
  "description": "testing lab",
  "main": "generateMap.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "person",
  "license": "ISC"
}

CodePudding user response：

You should export your class as bellow:


// adds an epicenter for an earthquake which can be placed on the board
class Epicenter {
    constructor(lat, long, magnitude, width) {
      this.lat = lat;
      this.long = long;
      this.magnitude = magnitude;
      this.width = width;
    }

    shiftMagnitude(){
      this.magnitude = Math.floor(Math.random(10) this.magnitude);
      console.log('Magnitude of epicenter has changed')
    }
  }
module.exports = Epicenter;

the config "type": "module" is for ES modules support on nodejs packages. so other packages could handle using the package with native import of last Node.js versions.