JS code speed tests

docs.md

Looping through elements

http://jsben.ch/UgRvN

• Accesses length property every loop.
• Accesses length property only once and saves it into a constant.
• Uses forEach method.

Removing an element of an array

http://jsben.ch/Io731

• array.splice.
• array.filter.
• Manually looping through each of the element to create a new array.

Notes

• Unlike array.filter, array.splice mutates the original array. So these two have different use cases. http://jsben.ch/DA7U2 compares array.filter and a regular for-loop.

array.map vs for-loop

http://jsben.ch/coXD5

array.forEach vs for-loop

http://jsben.ch/XuoTX

for-loop vs while-loop

http://jsben.ch/GjSyQ

Checking if object has a particular key

• in operator
• strict comparison operator
• Object.hasOwnProperty
• object.key expression

http://jsben.ch/EwSf2

Credits to who ever made it. I simply added a new code block.

Checking if an element exists in an array

http://jsben.ch/JLngr

• array.indexOf
• array.includes
• for-loop
• while-loop