Benchmarking Javascript Loops and Methods

00-benchmarking-javascript-loops-part-1.js

//

01-examples-of-primitive-arrays.js

// Examples of primitive arrays

let namesArray = ['Abe', 'Beth', 'Cody', 'Daniel'];
let textArray = ['Dog', 'Cat', 'Horse', 'Cow'];
let numbersArray = [1, 2, 3, 4];

02-starter-code.js

// starter-code.js
// Objectives:
// 1. Find the value 7
// 2. Find the index of 7

const OBJECTIVE_NUMBER = 7;

let arr = [1, 2, 3, 4, 5, 6, 7, 8, 9];

let foundValue;
let foundIndex = -1;

03-for.js

// for
// Using array and variables from base code block above… (starter-code.js)

for (let index = 0; index < arr.length; index++) {
  const value = arr[index];
  if(value === OBJECTIVE_NUMBER) {
    foundValue = value;
    foundIndex = index;
    break;
  }
};

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;

04-for-of.js

// for...of
// Using array and variables from base code block above… (starter-code.js)

for (const value of arr) {
  if(value === OBJECTIVE_NUMBER) {
    foundValue = value;
  }
};

console.log(foundValue); // expected output: 7;

05-forEach.js

// forEach
// Using array and variables from base code block above… (starter-code.js)

arr.forEach((value, index) => {
  if(value === OBJECTIVE_NUMBER) {
    foundValue = value;
    foundIndex = index;
  }
});

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;

06-while.js

// while
// Using array and variables from base code block above… (starter-code.js)
let length = arr.length;
let index = 0;

while(index < length) {
  const value = arr[index];
  if(value === OBJECTIVE_NUMBER) {
    foundValue = value;
    foundIndex = index;
    index = length - 1;
  }
  index++;
};

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;

07-do-while.js

// do...while
// Using array and variables from base code block above… (starter-code.js)

let length = arr.length;
let index = 0;

do {
  const value = arr[index];
  if(value === OBJECTIVE_NUMBER) {
    foundValue = value;
    foundIndex = index;
    index = length - 1;
  }
  index++;
} while (index < length);

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;

08-find.js

// find
// Using array and variables from base code block above… (starter-code.js)

foundValue = arr.find((value, index) => {
  if(value === OBJECTIVE_NUMBER) {
    foundIndex = index;
    return true;
  }
  return false;
});

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;

09-findIndex.js

// findIndex
// Using array and variables from base code block above… (starter-code.js)

foundIndex = arr.findIndex((value, index) => {
  if(value === OBJECTIVE_NUMBER) {
    foundValue = value;
    return true;
  }
  return false;
});

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;

10-indexOf.js

// indexOf
// Using array and variables from base code block above… (starter-code.js)

foundIndex = arr.indexOf(OBJECTIVE_NUMBER);

console.log(foundIndex); // expected output: 6;

11-lastIndexOf.js

// lastIndexOf
// Using array and variables from base code block above… (starter-code.js)

foundIndex = arr.lastIndexOf((value, index) => {
  if(value === OBJECTIVE_NUMBER) {
    foundValue = value;
    return true;
  }
  return false;
});

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;

12-includes.js

// includes
// Using array and variables from base code block above… (starter-code.js)
// Not very useful at finding the value or index, but it is nice to know if it is there. :)

let valueExists = arr.includes(OBJECTIVE_NUMBER);

console.log(valueExists) // expected output: true;

13-map.js

// map
// Using array and variables from base code block above… (starter-code.js)
// This an anti-pattern when used ONLY to loop and find a value/index rather than the intended function of returning a new array.

arr.map((value, index) => {
  if(value === OBJECTIVE_NUMBER && foundIndex !== -1) {
    foundValue = value;
    foundIndex = index;
  }
});

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;

14-filter.js

// filter
// Using array and variables from base code block above… (starter-code.js)
// This an anti-pattern when used ONLY to loop and find a value/index rather than the intended function of returning a new array.

foundValue = arr.filter((value, index) => {
  if(value === OBJECTIVE_NUMBER && foundIndex !== -1) {
    foundIndex = index;
  }
})[0];

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;

15-reduce.js

// reduce
// Using array and variables from base code block above… (starter-code.js)
// This an anti-pattern when used ONLY to loop and find a value/index rather than the intended function of returning a new value.

arr.reduce((accumulator, value, index) => {
  if(value === OBJECTIVE_NUMBER && foundIndex !== -1) {
    foundValue = value;
    foundIndex = index;
  }
  return accumulator;
});

console.log(foundValue); // expected output: 7;
console.log(foundIndex); // expected output: 6;