I was wondering if there is a better way to get the Index of Key whose values contain the given value, otherwise it returns Null. In the example below it does what i need, but wasn't sure not sure if there was a simpler way of writing it. I know javascript's syntax is quite powerful and I'm not as familiar with it as others may be.
const sets = {
"Set 1": [2, 3],
"Set 2": [4, 5],
"Set 3": [6]
}
function getValueSetIndex(val) {
let count = 0
for (const [key, values] of Object.entries(sets)) {
if (values.includes(val)) {
return count;
}
count += 1
}
return null
}
console.log(getValueSetIndex(4))
console.log(getValueSetIndex(20))const sets = {
"Set 1": [2, 3],
"Set 2": [4, 5],
"Set 3": [6]
}
const needle = 5;
Object.values(sets).findIndex(a => a.find(b => b === needle))
returns position number or -1
const keyIndex = (obj, value) => {
const index = Object.keys(obj).findIndex(key => obj[key].includes(value));
return index > -1 ? index : null;
}
console.log(keyIndex(sets, 8));
I can see where you're coming from. It's often useful to consider how you might eliminate for loops even if you end up using them.
How do you like this version?:
const sets = {
"Set 1": [2, 3],
"Set 2": [4, 5],
"Set 3": [6]
}
const newGetValueSetIndex = val => {
const result = Object.values(sets)
.findIndex(
values => values.includes(val)
)
return result === -1
? null
: result
}
console.log(newGetValueSetIndex(4))
console.log(newGetValueSetIndex(20))