Finding the key in a map, given the value

Question

Hi I have a map like this :

[this:0, is:1, a:2, file:3, anotherkey:4, aa:5]

I wish I could find the key\'s given the value

Answer 1

def expect = 5
def m = ['this':0, is:1, a:2, file:3,  aa:5]
def r = m.collectMany{ k,v -> (v == expect) ? [k] : []}

// Result: [aa]