Lambda expression objects in Painless

Elastic Stack Elasticsearch
1

I have a closure object in a groovy script that I'm trying to port to painless. What is the proper syntax to do this?

closure object is something like:
> def myClosure
> myClosure = { oneMap, otherMap ->
> ...
> [output 1, output2]
> }
> outputList = myClosure(inMap1, inMap2)

2

Painless does not have closures like groovy. Lambdas are just like in java: they are an anonymous implementation of a functional interface. Here I think you are looking for functions: https://www.elastic.co/guide/en/elasticsearch/painless/master/painless-syntax.html#functions