var name = "value" var map = { // Primary. name: name, 1: true, // Call. name.count: name.count, name[0]: name[1], // Unary. -1: -2, ~3: !false, // Allow any expression for a value. "key": true ? 1 : 2 } System.print(map[name]) // expect: value System.print(map[1]) // expect: true System.print(map[name.count]) // expect: 5 System.print(map[name[0]]) // expect: a System.print(map[-1]) // expect: -2 System.print(map[~3]) // expect: true System.print(map["key"]) // expect: 1