/
map.js
35 lines (34 loc) · 993 Bytes
/
map.js
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const eqArrays = function(a, b) {
if (a.length !== b.length) {
return false;
} else {
for (let i = 0; i < a.length; i++) {
if (a[i] !== b[i]) {
return false;
}
}
return true;
}
};
const assertArraysEqual = function(a, b) {
if (eqArrays(a, b)) {
console.log(`✅✅✅ Assertion Passed: ${a} === ${b}`);
} else {
console.log(`🛑🛑🛑 Assertion Failed: ${a} !== ${b}`);
}
};
const map = function(array, callback) {
const results = [];
for (let item of array) {
results.push(callback(item));
}
return results;
};
const words = ["ground", "control", "to", "major", "tom"];
const results1 = map(words, word => word[0]);
assertArraysEqual(results1, ["g", "c", "t", "m", "t"]);
const results2 = map(words, word => word.length);
assertArraysEqual(results2, [6, 7, 2, 5, 3]);
const results3 = map(words, word => word.toUpperCase());
assertArraysEqual(results3, ["GROUND", "CONTROL", "TO", "MAJOR", "TOM"]);
module.exports = map;