Разница в двух массивах lodash
_.difference([2, 1], [2, 3]);
// => [1]
Bright Beetle
_.difference([2, 1], [2, 3]);
// => [1]export const groupArrayBy = (arr, groupBy) => {
let newArr = []
arr.map((item) => {
if(item[groupBy]) {
let finded = newArr.filter((newItem) => newItem[groupBy] === item[groupBy])
if(finded.length > 0) {
finded[0].products.push(item)
} else {
newArr.push({category: item[groupBy], products: [item]})
}
}
})
return newArr
}
let arr = [{
"birthdate": "1993",
"name": "Ben"
},
{
"birthdate": "1994",
"name": "John"
},
{
"birthdate": "1995",
"name": "Larry"
},
{
"birthdate": "1995",
"name": "Nicole"
},
{
"birthdate": "1996",
"name": "Jane"
},
{
"birthdate": "1996",
"name": "Janet"
},
{
"birthdate": "1996",
"name": "Dora"
},
];
const res = arr.reduce((ac, a) => {
let temp = ac.find(x => x.birthdate === a.birthdate);
if (!temp) ac.push({ ...a,
name: [a.name]
})
else temp.name.push(a.name)
return ac;
}, [])
console.log(res);Creates an object composed of keys generated from the results of running
each element of collection thru iteratee. The order of grouped values is
determined by the order they occur in collection. The corresponding value
of each key is an array of elements responsible for generating the key.
The iteratee is invoked with one argument: (value).
_.groupBy([6.1, 4.2, 6.3], Math.floor);
// => { '4': [4.2], '6': [6.1, 6.3] }
// The `_.property` iteratee shorthand.
_.groupBy(['one', 'two', 'three'], 'length');
// => { '3': ['one', 'two'], '5': ['three'] }_.defer(function(stamp) { console.log(_.now() - stamp);}, _.now());// => Logs the number of milliseconds it took for the deferred invocation.