Prompt: Create a function prioritize that accepts an array and a callback. The callback will return either true or false. prioritize will iterate through the array and perform the callback on each element, and return a new array, where all the elements that yielded a return value of true come first in the array, and the rest of the elements come second.
CODE:
function prioritize(array, callback) {
return array.reduce((accum, item) => {
if (callback(item)) {
accum[0].push(item)
} else {
accum[1].push(item)
}
return accum;
}, [[], []])
}
// Uncomment these to check your work!
function startsWithS(str) { return str[0].toLowerCase() === 's'; } //boolean, should be true or false
const tvShows = ['curb', 'rickandmorty', 'seinfeld', 'sunny', 'friends'] // array
console.log(prioritize(tvShows, startsWithS)); // should log: ['seinfeld', 'sunny', 'curb', 'rickandmorty', 'friends']I am having trouble figuring out how to merge the nested array that 'accum' returns to have the output return ['seinfeld', 'sunny', 'curb', 'rickandmorty', 'friends']. Any tips on how to go about solving this?
You just have to flatten the returned result:
function prioritize(array, callback) {
return array.reduce((accum, item) => {
if (callback(item)) {
accum[0].push(item)
} else {
accum[1].push(item)
}
return accum;
}, [[], []]).flat();
}
// Uncomment these to check your work!
function startsWithS(str) { return str[0].toLowerCase() === 's'; } //boolean, should be true or false
const tvShows = ['curb', 'rickandmorty', 'seinfeld', 'sunny', 'friends'] // array
console.log(prioritize(tvShows, startsWithS)); // should log: ['seinfeld', 'sunny', 'curb', 'rickandmorty', 'friends']