Using .size === 26 could be problematic without filtering for letters only. a sentence may include punctuation or numbers, which the Set will take as unique elements, potentially making .size === 26 as true or even .size > 26 even though not all letters are present.

I want to use it but i forgot its name and used methods ;(

so many array traversals

so clean

impressive

that's a good way to do it, thanks i learned something!

Теперь буду знать про every(

woahhhhhhhh that is amazing

все правильно работает

i agree for this solution. i'm never thinking this before. thanks

nice, clean!

could add it but null undefined etc are not booleans

The idea is that booleans only have two values. true and false. If the entered boolean is true it outputs "Yes" if the entere boolean is false it outpits "no" There isnt even any calculation required here. It just directly returns Yes or No depending on whats entered.