Conditional array as a parameter inside array

Question

I have this code:

const obj = new plugin.process({
  extensions: [...bindings, a, b]
});

Is there anyway to make the bindings optional based on another parm?

Say I have a boolean flag

 const obj = new plugin.process({
      extensions: [...bindings && myFlag, a, b]
    });

Any ideas?

Just construct the array before the .process() call and don't squeeze everything in one fanzy line of code — Andreas
– Andreas, Commented Jan 11, 2022 at 8:32

Trisma · Accepted Answer · 2022-01-11 13:40:57Z

1

You could simply construct the array before passing it into process.

First create your default array, this could be:

const extensions = [a, b]

Then add an extra condition in case your boolean is true:

if(myFlag) {
  extensions.push(...bindings)
}

Combining this together:

const extensions = [a, b]

if(myFlag) {
  extensions.push(...bindings)
}

const obj = new plugin.process({
  extensions
});

If bindings need to be added before a and b, we can write logic like this:

const extensions = []

if(myFlag) {
  extensions.push(...bindings)
}

extensions.push(a, b)

const obj = new plugin.process({
  extensions
});

answered Jan 11, 2022 at 8:36

Trisma

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3 Comments

The content of bindings has to be placed before a and b

@Andreas Added some more information

@Andreas bindings will be added before a and b since you first push bindings, then a and b

Yash Sonalia · Accepted Answer · 2022-01-11 10:02:35Z

0

Use this

const obj = new plugin.process({
  extensions: [
    ...bindings,
    ...(myFlag ? [a, b] : [])
  ]
});

answered Jan 11, 2022 at 10:02

Yash Sonalia

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This will work, but it's bad practice in general. It's not because it's compact that it's good. It's harder to read and understand what is going on.