Can't use ES6 import syntax

Question

I'm trying to use the ES6 import syntax and keep running into errors. This is my data type,

class UnionFind{
    constructor(n){
        this.items = n;
    }

    union(p, q){

    }

    connected(p, q){

    }

    find(p){

    }

    count(){

    }

}
export default UnionFind

Saved in a file UnionFind.js

This the calling client,

import { UnionFind } from './unionFind';

const readline = require('readline');

const rl = readline.createInterface({
    input:process.stdin,
    output:process.stdout,
    terminal:false

});

uf = new UnionFind(10)

rl.on('numbers', function (line) {
    arr = number.split(' ')

    console.log(arr);
});

This is saved in a file client.mjs

This is how I'm running it,

node --experimental-modules union-find/client.mjs

I get the following error,

(node:13465) ExperimentalWarning: The ESM module loader is experimental.
file:///Users/mstewart/Dropbox/data-structures-algorithms-princeton/union-find/client.mjs:1
import { UnionFind } from './unionFind';
         ^^^^^^^^^
SyntaxError: The requested module does not provide an export named 'UnionFind'
    at ModuleJob._instantiate (internal/modules/esm/ModuleJob.js:89:21)
    at <anonymous>

What am I doing wrong here?

Answer 1

In this case, use

       import UnionFind from './UnionFind.js';

if you declared

       export class UnionFind{ ....

then you use

import { UnionFind } from './UnionFind.js';

Also take a look at the file name: UnionFind.js . You are using './unionFind'. This is case sensitive