/
map.js
51 lines (38 loc) · 1.08 KB
/
map.js
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const eqArrays = function(arr1, arr2) {
if (arr1.length !== arr2.length) {
return false;
}
for (let i = 0; i < arr1.length; i++) {
if (arr1[i] !== arr2[i]) {
return false;
}
}
return true;
};
const assertArraysEqual = function(arr1, arr2) {
let pass = eqArrays(arr1, arr2);
if (pass) {
console.log(`✅✅ Assertion Passed: ${arr1} === ${arr2}`);
} else {
console.log(`❌❌ Assertion Failed: ${arr1} !== ${arr2}`);
}
};
//map function
// take in array to map and callback function
// return new array based on results of callback function
const words = ["ground", "control", "to", "major", "tom"];
const map = function(array, callback) {
const results = [];
for (let item of array) {
results.push(callback(item));
}
return results;
};
const results1 = map(words, word => word[0]);
const results2 = map([], word => word[0]);
const results3 = map([1, 2, 3], num => num * 2);
//tests
assertArraysEqual(results1,['g', 'c', 't', 'm', 't']);
assertArraysEqual(results2,[]);
assertArraysEqual(results3,[2, 4, 6]);
module.exports = map;