Iterate.groovy

// Haskell-style iterate function in Groovy

Closure iterate(def value, Closure nextValue) {
    return { value = nextValue value }
}


// use for iteration
def iter = iterate(0) { it + 1}
5.times {
    println iter()
}

// use for fixpoint calculation
def fix = iterate(1.0) { Math.cos it}
while (fix() != fix()) {}
println fix()