Say you have a long list, maybe filled with some simple objects with key and val fields. Imaginary you wants to:

1. Know if any items in the list contain the value 'value 1'
2. Run some additional methods if the item exists in the list
3. Save a reference to a particular value from the item
4. Stop the search early

Using the steps above, let's implement a solution. First, some top level bits to give us context:

// AKA: myHugeListIDontWantToIterateOverEntirely
const bigListBigDeal = [
  { key: 'one', val: 'value 1' },
  { key: 'two', val: 'value 2' },
  { key: 'three', val: 'value 3' },
  // + 5000 more entries...
]

// We'll use this highly imaginary code in just a moment
function specialSideEffect(val) {
  const dbClient = require('db').connect()

  return {
    operationStatus: dbClient.commitSuperImportantThing({ importantOption: val })
  }
}

Next, let's put Array.some() to work, implementing our outline from above:

let returnVal = null
const searchVal = 'value 1'

// 1) Ask if any items in the list contains the value `"value 1"`
bigListBigDeal.some(item => {
  if (item.val == searchVal) {
    // 2) Run some additional methods if the item exists in the list
    // 3) Save a reference to a particular value from the item
    returnVal = specialSideEffect(item.val)
    // 4) Stop the search early by returning true from Array.some()
    return true
  }
})

// 5) Robust & full-flavored error handling
if (returnVal === null) {
  throw new Error(`Could not find ${searchVal}, even in the biggest of lists`)
}

There we have it! A wonderfully contrived snippet of code, created with the singular goal of showcasing my love for Array.some().