javascript Zadanie

Posted 2021-05-03

Zdefiniować wyrażenie, które będzie zwracać sumę wartości kluczy `value`, których `state = true`.

```JavaScript
const a = [
  {value: 5, state: true},
  {value: 2, state: false},
  {value: 3, state: true}
];

const b = ...
console.log(b) // 8 (5+3)
```

const a = [{value: 10, state: true}, {value: 2, state: false}, {value: 3, state: true}];

const sum = array => (array.reduce(
  (total, object) => (total + (object.state && object.value)), 0));

console.log(sum(a)); // 13

const a = [
  { value: 5, state: true },
  { value: 2, state: false },
  { value: 3, state: true },
];

const getSum = arr =>
  arr.reduce((prev, current) => (current.state ? prev + current.value : prev), 0);
  
console.log(getSum(a)); // 8

const b = a.filter((val) => val.state).map((val) => val.value || val.foo).reduce((a, b) => a + b, 0); 

const a = [{value: 5, state: true}, {value: 2, state: false}, {value: 3, state: true}];
const b = a.filter(i => i.state).reduce((x,y) => x + y.value, 0);
console.log(b); // 8