I have been working on a shopping list application in React but have ran into a problem with exporting a regular JavaScript function from a file called webscrape.js into my react App.js I have tried multiple different ways of exporting but I keep getting this error.
Thanks to any help in advance.
Module not found: Can't resolve 'readline' in
'C:\Users\USERNAME\Desktop\Programming-Projects\Counter
App\counter-app\node_modules\puppeteer\lib\cjs\puppeteer\node'
This is the end of my webscrape file where I export a test function
function testExport(){
console.log("Test Export");
}
function testExport2(){
console.log("Test Export 2");
}
export {testExport, testExport2}
This is the start of my App.js where I import and try using the function
import NavBar from "./components/navbar";
import PriceBar from "./components/pricebar";
import "./App.css";
import Counters from "./components/counters";
import fs from 'fs';
import data from "./shoppingData.json";
import {testExport, testExport2} from "./webscrape.js";
//test export
testExport();
You should use export default {testExport, testExport2}.
But, looking throught your errors, seems like the error it's related to puppeter. Do you have puppteer added to your node_modules? Did you make a npm i?
Try:
export const testExport = () => {
console.log("Test Export");
}
export const testExport2 = () => {
console.log("Test Export 2");
}
Related
I have the following folder structure
I want to import both MessageList.tsx and MessageSent.tsx inside my Chat.tsx
// Chat.tsx
import React from 'react'
import {MessageList, MessageSent} from "./components/"
type Props = {}
const Chat= (props: Props) =\> {
return (
<div\>Chat</div>
)
}
export default Chat`
// MessageSent.tsx
import React from 'react'
type Props = {}
const MessageList = (props: Props) => {
return (
<div>MessageList</div>
)
}
export default MessageList
MessageList.tsx is similar to MessageSent,tsx, only the name of the components is different
However, when I try to do the import of these two components {MessageList, MessageSent} I get the following error:
** Cannot find module './components/' or its corresponding type declarations.**
Why is that?
Tried different paths besides "./components/", even with full path.
You can either import the components one by one
import MessageSent from "./components/MessageSent"
import MessageList from "./components/MessageList"
or create an index directory file (index.ts)
import MessageSent from './MessageSent'
import MessageList from './MessageList'
export { MessageSent, MessageList }
To be able to import from components you need index.ts file in components folder.
// index.ts
export * from './MessageList';
export * from './MessageSent';
Add a new file named index.ts inside your components folder
Then write this in the index.ts
export * from './MessageList.tsx';
export * from './MessageSent.tsx';
This Meteor app has a template event that maks a Meteor.call, and is causing browser error Cannot find module 'server/plateCheck.js'. The file responsible is:
//app/imports/api/vehicles/methods.js
import { Meteor } from 'meteor/meteor'
import { Vehicles } from './vehicles.js'
import { plateCheck } from "../server/plateCheck.js"; //<<<<<<<<<<
Meteor.methods({
'extractPlateData': function (plate) {
console.log('method called: ', plate)
plateCheck(plate)
}
)},
//app/imports/api/vehicles/server/plateCheck.js
import {Vehicles} from '../imports/api/vehicles/vehicles.js'
const plateCheck = async (plateNumber) => {...}
module.exports = plateCheck;
meteor list includes ecmascript 0.15.1
Why is this and isn't the export/import correct as stated? How to get read of the error? Thanks.
Your relative path is wrong. The server folder is in the same directory as methods.js, so you'll need to import
import { plateCheck } from "./server/plateCheck.js";
Or you can make all imports absolute:
//app/imports/api/vehicles/methods.js
import { plateCheck } from "/imports/api/server/plateCheck.js";
...
//app/imports/api/vehicles/server/plateCheck.js
import {Vehicles} from '/imports/api/vehicles/vehicles.js'
Currently in my directory I have App.js and startMenu.js as two separate files.
I would like to access startMenu.js in my App.js file with the correct React formatting.
Currently I can call the function startMenu() using typical javascript syntax, but I for some reason cannot get the React syntax {startMenu} to work. Any ideas would be appreciated.
My code:
import React from "react";
import startMenu from './startMenu';
import credits from "./credits";
var param = 'start';
class App extends React.Component {
renderSwitch(param) {
switch(param) {
case 'credits':
return credits();
default:
/*LINE IN QUESTION */
return startMenu();
}
}
render() {
return (
<div>
{this.renderSwitch(param)}
</div>
);
}
}
export default App;
Thanks!
It is depending how you are exporting your function.
If is doing this:
export default startMenu;
Then you might import that way:
import myFunction from './path';
That way the name does it care. You can call your function with any name when you are exporting by default.
But if you are exporting that way:
export { startMenu };
or
export startMenu;
So than you need import your function by your reall name, and if you are exporting just using export word, all members will be inside an object.
So you need do that:
import MyFunctions from './path';
or doing a import destruction
import { startMenu } from './path';
You'll need to properly export that function:
export function startMenu(...) { ... }
Then import it:
import { startMenu } from './startMenu';
If that's the only thing exported you can always export default and it simplifies the import.
You can only import things that have been exported. Everything else is considered private and is off-limits.
The JSX syntax: {foo} means "Put this data here".
It doesn't mean "Call this variable as a function".
If you want to call it, you need to do so explicitly: {foo()}.
I do not understand how nodejs resolves import statements. I constantly get the cannot import before initialization error.
For example, I have a init module, which exports an async function and a couple of constants that it creates.
import init, { DATA_VALIDATION_POOL, QUEUE_POOL, IS_REPLAY_POOL } from './init.js';
and then app.js waits for the init function to run. init.js itself has imports as well, and some of them resolve and some of them fail. I do not understand why some fail and some import properly.
In this example, everything to the point of importing from ./utils/pool.js is working fine, but for whatever reason, it cannot import the contents of ./utils/dash.js.
./utils/dash.js doesn't import anything from ../init.js
init.js
...
// CREATE POOLS
...
export const QUEUE_POOL = createPool('QUEUE_POOL');
// EMOJI INTERACTIONS
...
registerEmojiInteraction(QUEUE_POOL, {
...
onAdd: goToPrevPage,
});
const init = async () => {
...
await createCoaches(allCoachIds);
};
import { rankEmojis, raceEmojis, vsRaceEmojis } from './Emojis.js';
import { registerEmojiInteraction, onAddHelper } from './utils/emojiInteraction.js';
import { createPool } from './utils/pool.js';
import {
finishedCoachingStudent,
goToPrevPage,
selectStudent,
goToNextPage,
} from './utils/dash.js';
import { createCoaches } from './utils/coach.js';
export default init;
Hello i am just learning ReactJs, I am trying to import a module from a sub folder in react, here is my folder structure
-src
---components
-----layout
-------Header.js
-------Navigation.js
-----fakeAuth.js
From the Header.js module, i am trying to import the fakeAuth from the parent (component), but it seems it can't call module or am i just missing something?
I already tried the following
import fakeAuth from './fakeAuth'
import fakeAuth from '././fakeAuth'
import fakeAuth from '../../fakeAuth'
Still no luck, i know this will be easy for some. Thanks
here i my fakeAuth.js, which is from the react-router-dom tutorial.
module.exports = {
isAuthenticated: false,
authenticate(cb) {
this.isAuthenticated = true;
setTimeout(cb, 100); // fake async
},
signout(cb) {
this.isAuthenticated = false;
setTimeout(cb, 100);
}
};
It should be import fakeAuth from '../fakeAuth'
You just have to go 1 folder up where you have fakeAuth.js file. adding '..' does that.
Since you're using module.exports you can import in the following fashion inside Header.js:
import { isAuthenticated, authenticate, signout } from "../fakeAuth";
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