npm pack for Frontend

browser-sync

npm install -g browser-sync

https://browsersync.io/

json server

npm install -g json-server

https://github.com/typicode/json-server

формат телефоного номера

'123456789'.replace(/(\d+)(\d{3})(\d{2})(\d{2})/, "$1 $2-$3-$4")

12 345-67-89

Клик вне попапа

if (!popup.contains(e.target)){
popup.hidden = true;
}

оптимизация циклов по скорости

for(var i = items.length; i--;){  items[i]}

var j = items.length;while(j--){   items[j]}

var j = items.length-1;do{   items[j]}while(j--)

JS table of types plus types

Different result types of + by operand types

-------------------------------------------------------------------------------------------
            | undefined | boolean | number | string | function | object | null   | array  | 
-------------------------------------------------------------------------------------------

undefined   | number    | number  | number | string | string   | string | number | string | 

boolean     | number    | number  | number | string | string   | string | number | string | 

number      | number    | number  | number | string | string   | string | number | string | 

string      | string    | string  | string | string | string   | string | string | string | 

function    | string    | string  | string | string | string   | string | string | string | 

object      | string    | string  | string | string | string   | string | string | string | 

null        | number    | number  | number | string | string   | string | number | string | 

array       | string    | string  | string | string | string   | string | string | string | 

-------------------------------------------------------------------------------------------