Hi. Anyone could tell me what this type means? `val results: (MutableList<(MutableMap<String!,...

# getting-started

[blindbox]

Hi. Anyone could tell me what this type means? val results: (MutableList<(MutableMap<String!, Any!>..Map<String!, Any!>?)>..List<(MutableMap<String!, Any!>..Map<String!, Any!>?)>?) especially the double dots. The function that returns that type was actually returning this java type, List<Map<String, Object>>

[voddan]

@blindbox it's a bad case of a platform type http://kotlinlang.org/docs/reference/java-interop.html#null-safety-and-platform-types

[voddan]

The .. means it can anything in between those 2 types

[voddan]

Docs probably should mention that

[blindbox]

Interesting. Is this type specifically due to java interop, or does it also mean that we can define a type that is as such?

[diesieben07]

It's just for Java interop, you can't declare it.

[karelpeeters]

@blindbox Nope, there's no special syntax for them, they're just a notation for tools and error messages.
They're called Platform Types, see https://kotlinlang.org/docs/reference/java-interop.html#null-safety-and-platform-types