| /** | |
| * Write a JavaScript function that takes a number n and returns the sum of the even numbers from 1 to n. | |
| */ | |
| function firstFunc(n) { | |
| let result = 0; | |
| for (let index = 1; index <= n; index++) { | |
| if (index % 2 === 0) { | |
| result += index; | |
| } | |
| } |
Closure is when a function "remembers" its lexical scope even when the function is executed outside that lexical scope. (IMO: just a stupid function returning another partially applied function).
Variable and function declarations are put into memory during the compile phase, but stays exactly where you typed it in your coding. There is no physically lifting to the top of the file at all.
| const fullAlphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'; | |
| const restrictedAlphabet = 'BCDFGHJKLMNPQRSTVWXZbcdfghjklmnpqrstvwxz'; | |
| const threadPrefix = 'thread-'; | |
| const messagePrefix = 'msg-'; | |
| const isWhitespace = str => /^[\s\xa0]*$/.test(str); | |
| const isInvalidString = str => str ? (str.indexOf(threadPrefix) !== -1 || str.indexOf(messagePrefix) !== -1) : false; | |
| const encode = function(str) { | |
| if (isWhitespace(str)) return str; |