// Ranges
1900..1999  // twentieth century (inclusive Range)
2000..<2100 // twenty-first century (exclusive Range)
'A'..'D'    // A, B, C, and D
10..1       // 10, 9, 8, ..., 1
'Z'..'X'    // Z, Y and X

// using expressions in ranges
def start = 10
def finish = 20
start..finish+1 // 10, 11, 12, ...., 20, 21