# Server Side Kotlin-09

**partition()** filters a collection by a predicate and makes Pair of Lists, the first list containing elements from collection that matches  the predicate and the second one containing rest of the element.
```   
val games = listOf("unity", "unreal", "godot", "bevy")
val (match, rest) = games.partition { it.length > 4 }
println(match)
println(rest) 
```    
output    
[unity, unreal, godot]   
[bevy]     
**any() and none()** can  be used without a predicate: in this case they just check the collection emptiness.  
```    
val games = listOf("unity", "unreal", "godot", "bevy")
val empty = emptyList<String>()

println(games.any())
println(empty.any())

println(games.none())
println(empty.none())  
```   
output     

`true`   
`false`   
`false`    
`true `    

**any()** returns true if at least one element matches the given predicate.

**none()** returns true if none of the elements match the given predicate.

**all()** returns true if all elements match the given predicate. Also all() returns true when called with any valid predicate on an empty collection. It is known as **vacuous truth**.
```
val games = listOf("unity", "unreal", "godot", "bevy")

println(games.any { it.endsWith("y") })
println(games.none { it.endsWith("a") })
println(games.all { it.endsWith("e") })
// vacuous truth
println(emptyList<Int>().all { it > 4})   
```
output    

true   
true   
false    
true