Add two maps in Groovy while summing up values for common keys

Question

I have two maps in Groovy [a: 1, b: 2] and [b:1, c:3] and would like to create from them a third map [a: 1, b: 3, c: 3]. Is there a Gr

Answer 1

def merge(map1, map2) { 
    def add = { map, entry -> map << entry }
    map2.inject(map1.inject([:], add), add)
}