Function unionBy

unionBy<T, U>(a: T[], b: T[], predicate: (item: T) => U): T[]
Union two arrays by predicate

两个数组的并集，根据 predicate 函数进行比较
Type Parameters
- T
- U
Parameters
- a: T[]
- b: T[]
- predicate: (item: T) => U
Returns T[]
Example
```
unionBy([1, 2, 3], [2, 4, 5, 6], (item) => item % 2) // => [1, 2, 3, 4, 5, 6]
unionBy([1, 2], [3, 4], (item) => item % 2) // => []
```
- Defined in src/array/union.ts:33