transducer-api-core-js.js

const isEven = value => value % 2 === 0;

const coreJs = array => {
  // starts from 0
  let sum = 0;
  // iterates over array
  for (let i = 0; i < array.length; i++) {
    // transforms value to value + 1
    const result = array[i] + 1;
    // ignores odd values
    if (isEven(result)) {
      // applies addition
      sum += result;
    }
  }
  return sum;
};

const ages = [16, 23, 24]
coreJs(ages)  // 24