NodeJS variable not defined

Question

I can't seem to find a problem why this is not working. When I go to localhost:3000 I get this error ReferenceError: pixwords is not defined

app.get('/', (req, res) => {
Word.find().then((pixwords) => {
    if(!pixwords) {
     return res.send('No text available');
    }
});
res.render('index.hbs', {pixwords});
});

This is index.hbs:

{{#each pixwords}}
    {{this.text}}
{{/each}}

`pixwords` is only defined inside the `Word.find().then()` context, not outside. — Zenoo, Sep 17 '18 at 12:56
@ThomasLombart It's a result from a `Word` model, so it contains all the words from collection. — labas GamePage visogero, Sep 17 '18 at 12:56
You are calling res.render immediately after calling Word.find. You need to call render in the callback of then() — UpTheCreek, Sep 17 '18 at 12:56
The answers to the linked questions address the real issue here (trying to use the result of an asynchronous call before the call completes), but note that separately, there's a quite basic scope issue. Obviously, you can't use a variable or parameter outside the function in which it's declared. — T.J. Crowder, Sep 17 '18 at 12:59

Luca Kiebel · Answer 1 · 2018-09-17T12:58:02.833

2

pixwords is only defined in the callback function of Word.find().then(), you can only use it there:

app.get('/', (req, res) => {
  Word.find().then((pixwords) => { // <-- this declares pixwords
    if (!pixwords) {
      return res.send('No text available');
    }
    res.render('index.hbs', { // <-- move the call in the .then
      pixwords
    });
  });
  // anything here is executed before Word.find has finished running
});

edited Sep 17 '18 at 12:58

answered Sep 17 '18 at 12:56

Luca Kiebel

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This is one of the most often-repeated duplicates on SO. We really don't need *another* answer to it. – T.J. Crowder Sep 17 '18 at 12:57

NodeJS variable not defined

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