var list=['abc','ab','a','c','bc','abcdef','cdf','opq']
output:-
var object={
['a','c'],
['ab','bc'],
['abc','cdf','opq'],
['abdcef']}
Try this :
let list = ['abc', 'ab', 'a', 'c', 'bc', 'abcdef', 'cdf', 'opq'];
let temp = {};
list.map(function (item) {
!temp.hasOwnProperty(item.length) ? temp[item.length] = [item] : temp[item.length].push(item);
});
let output_dict = {'output': Object.values(temp)};
console.log(output_dict)