|
|
|
|
|
// Swift 4 builtin data types:
|
|
|
|
|
|
//
|
|
|
|
|
|
// * Int or UInt (Int32, Int64, UInt32, UInt64)
|
|
|
|
|
|
// * Float
|
|
|
|
|
|
// * Double
|
|
|
|
|
|
// * Bool
|
|
|
|
|
|
// * String
|
|
|
|
|
|
// * Character
|
|
|
|
|
|
// * Optional − a variable that can hold either a value or no value.
|
|
|
|
|
|
// * Tuples
|
|
|
|
|
|
//
|
|
|
|
|
|
// | -------|-------------------|-----------------------------------------------|
|
|
|
|
|
|
// | Type | Typical Bit Width| Typical Range |
|
|
|
|
|
|
// | -------|-------------------|-----------------------------------------------|
|
|
|
|
|
|
// | Int8 | 1byte | -127 to 127 |
|
|
|
|
|
|
// | UInt8 | 1byte | 0 to 255 |
|
|
|
|
|
|
// | Int32 | 4bytes | -2147483648 to 2147483647 |
|
|
|
|
|
|
// | UInt32 | 4bytes | 0 to 4294967295 |
|
|
|
|
|
|
// | Int64 | 8bytes | -9223372036854775808 to 9223372036854775807 |
|
|
|
|
|
|
// | UInt64 | 8bytes | 0 to 18446744073709551615 |
|
|
|
|
|
|
// | Float | 4bytes | 1.2E-38 to 3.4E+38 (~6 digits) |
|
|
|
|
|
|
// | Double | 8bytes | 2.3E-308 to 1.7E+308 (~15 digits) |
|
|
|
|
|
|
// | -------|-------------------|-----------------------------------------------|
|
|
|
|
|
|
|
|
|
|
|
|
// Type Aliases:
|
|
|
|
|
|
//
|
|
|
|
|
|
typealias Feet = Int
|
|
|
|
|
|
var distance: Feet = 100
|
|
|
|
|
|
print(distance)
|
|
|
|
|
|
|
|
|
|
|
|
// Type inference:
|
|
|
|
|
|
//
|
|
|
|
|
|
// varA is inferred to be of type Int
|
|
|
|
|
|
var varA = 42
|
|
|
|
|
|
print(varA)
|
|
|
|
|
|
//
|
|
|
|
|
|
// varB is inferred to be of type Double
|
|
|
|
|
|
var varB = 3.14159
|
|
|
|
|
|
print(varB)
|
|
|
|
|
|
//
|
|
|
|
|
|
// varC is also inferred to be of type Double
|
|
|
|
|
|
var varC = 3 + 0.14159
|
|
|
|
|
|
print(varC)
|
