I found that parentheses are not required when partial function used as parameter in Scala

```
val array = Array(2)
array.map(x => x + 1)
array.map { case x => x + 1 }
```

`{ case x => x + 1 }`

defines a partial function here, so it should be `array.map({ case x => x + 1 })`

, but there are no parentheses.So what happend here? Is that syntactic sugar?