Persistent undefined error in typescript import export

Question

There's already a LOT of questions about typescript in multiple files.. for instance, this one,

Interesting question and answer, I simplified and tested it, see below.. but whatever I try, I still get

Uncaught TypeError: Cannot read properties of undefined (reading 'A')

.. as does any other example of import/export in TypeScript I found online. Whatever I do, whatever object I try export (class, function, const) with or without using a module: I get the same error.

Maybe there is something wrong in my NPM/TSC/React configuration ? Should I change e.g. tsconfig.js when i want to use more than one typescript file in a project ? I'm lost, what do I miss ?

tsconfig.json

{ // TypeScript configuration file: provides options to the TypeScript 
  // compiler (tsc) and makes VSCode recognize this folder as a TS project,
  // enabling the VSCode build tasks "tsc: build" and "tsc: watch".
  "compilerOptions": {
   "target": "es5",            // Compatible with older browsers
   "module": "umd",            // Compatible with both Node.js and browser
   "moduleResolution": "node", // Tell tsc to look in node_modules for modules
   "sourceMap": true,          // Creates *.js.map files
   "jsx": "react",             // Causes inline XML (JSX code) to be expanded
   "strict": true,             // Strict types, eg. prohibits `var x=0; x=null`
   "alwaysStrict": true        // Enable JavaScript's "use strict" mode
  },
 "include": ["**/*.ts", "**/*.tsx"],
 "exclude": ["node_modules"]

}

first.tsx

const A ={
  val: 'A'
}    
export { A }

app.tsx

import { A } from "./first";

// ... other code

function reportPerson()
{
  console.log(A);
}

.. Both files translate to .js with TSC, but A is reported by the Google Chrome console as undefined,

Both tsx files are in the same directory, TSC converts them both to JS without any issue.

What's going on ?

Goodies · Accepted Answer · 2022-09-15 19:08:28Z

1

Thanks everyone for the advice (I didn't solve the above minimal example either..)

In order to properly link my stuff together, I've now put Parcel 2 to work,

https://www.npmjs.com/package/parcel

npm i parcel

This is basically a bundler, that allows separate ts files to be concatenated after they are compiled to Javascript and it will put everything in a \dist directory,

parcel build src/index.html

Based on a small react example, I put my first "modulized" little app in TypeScript to work. Then, with the help of expert advise, I proceeded with twgl.js, which is a great toolkit for Webgl2.

npm install twgl.js

This javascript library even has sub-modules.. and everything links fine now, I can access (all of?) twgl with

import * as twgl from "./twgl-full.js";

edited Sep 15, 2022 at 19:08

answered Sep 15, 2022 at 19:01

Goodies

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