groovy Memoize on closures


Example

Since Groovy 1.8 a convenient memoize() method is added on closures:

// normal closure
def sum = { int x, int y  ->
    println "sum ${x} + ${y}"
    return x + y
}
sum(3, 4)
sum(3, 4)
// prints
// sum 3 + 4
// sum 3 + 4

// memoized closure
def sumMemoize = sum.memoize()
sumMemoize(3, 4)
// the second time the method is not called 
// and the result it's take from the previous 
// invocation cache
sumMemoize(3, 4)
// prints
// sum 3 + 4