Suppose I have:
const apple = true
const pear = false
const coconut = true
I would like to have:
const activeFruits = ['apple', 'coconut']
How can I do something like this? This is what I've tried:
const activeFruits = [
apple ? 'apple' : '',
pear ? 'pear' : '',
coconut ? 'coconut' : '',
]
Then I have to filter out the empty string.
It works but doesn't seem to be to me the smartest way. Is there a better way?
One idea to have a dynamic way will be to have an object that contains your variables:
const fruits = {
apple: true,
pear: false,
coconut: true
};
const activeFruit = Object.keys(fruits).filter(key => !!fruits[key]);
console.log(activeFruit)Not sure if this is smarter or the smartest, but this is a different approach
You could wrap all of the fruits into an object, transform that object into key-value pairs (using Object.entries()), filter pairs which have value of true, and then map the pairs to get the keys
const apple = true
const pear = false
const coconut = true
const obj = {
apple,
pear,
coconut
}
const activeFruits = Object.entries(obj)
.filter(([_, value]) => value === true)
.map(([key, _]) => key)
console.log(activeFruits)To answer your question, I would do it like this:
if (apple) {
activeFruits.push('apple');
}
if (pear) {
activeFruits.push('pear');
}
if (coconut) {
activeFruits.push('coconut');
}
However, I would question the initial data structure you have and (if possible) change it to:
const fruits = {
apple: true,
pear: false,
coconut: true
};
Then get the answer like this:
const activeFruits = Object.keys(fruits).filter(key => !!fruits[key]);
