I was messing around with the random number generator code for Int and noticed that the API has two Range types, Range and ClosedRange. Upon further investigation I found that Swift supports even more range types. <\/p>\n
So currently the range types are Range, ClosedRange, PartialRangeFrom, PartialRangeUpTo, PartialRangeThrough and CountableRange.<\/p>\n
Range<\/strong><\/p>\n The Range<\/a> type is “a half-open interval from a lower bound up to, but not including, an upper bound”. Which basically means the ..< syntax, i.e.<\/p>\n In other words range<\/em> is from (and including) 1 to 100 (but not including 100).<\/p>\n We might write a function to handle this using the following syntax<\/p>\n ClosedRange<\/strong><\/p>\n The ClosedRange<\/a> type is “an interval from a lower bound up to, and including, an upper bound”. Which basically means the … syntax, i.e.<\/p>\n In other words range<\/em> is from (and including) 1 to 100 (and including 100).<\/p>\n We might write a function to handle this using the following syntax<\/p>\n PartialRangeFrom<\/strong><\/p>\n The PartialRangeFrom<\/a> type is “a partial interval extending upward from a lower bound”. Which uses … syntax, i.e.<\/p>\n We might write a function to handle this using the following syntax<\/p>\n PartialRangeUpTo<\/strong><\/p>\n The PartialRangeUpTo<\/a> type is “a partial half-open interval up to, but not including, an upper bound”. Which uses ..< syntax, i.e.<\/p>\n We might write a function to handle this using the following syntax<\/p>\n\r\nlet range = 1..<100\r\n<\/pre>\n
\r\n\/\/ usage rangeTest.range(1..<10)\r\nfunc range(_ r: Range<Int>) -> Void {\r\n print("\\(r.lowerBound), \\(r.upperBound)")\r\n}\r\n<\/pre>\n\r\nlet range = 1...100\r\n<\/pre>\n
\r\n\/\/ rangeTest.range(1...10)\r\nfunc range(_ r: ClosedRange<Int>) -> Void {\r\n print("\\(r.lowerBound), \\(r.upperBound)")\r\n}\r\n<\/pre>\n\r\nlet range = 0...\r\n<\/pre>\n
\r\n\/\/ rangeTest.range(..<10)\r\nfunc range(_ r: PartialRangeUpTo<Int>) -> Void {\r\n print("\\(r.lowerBound)")\r\n}\r\n<\/pre>\n\r\nlet range = ..<100\r\n<\/pre>\n
\r\n\/\/ rangeTest.range(..<10)\r\nfunc range(_ r: PartialRangeUpTo<Int>) -> Void {\r\n print("\\(r.upperBound)")\r\n}\r\n<\/pre>\n