[RECIPE]: distinct operation for array

Being web full stack developer after years of .NET work sometimes brings you to a blind alley. For example, such trivial thing as `.distinct()` function for array, which is not present in TS/JS. So, let's find out how to do the same.

const data: ItemType[] = [{id: 1}, {id: 1}, {id: 2}];

const distinctItems = data.reduce((result: ItemType[], current: ItemType) => {
	return result.some(x => x.id === current.id) ? result : result.concat([current]);
}, []);

Reduce has number of usages!