该-import-objc-header标志指定swiftc要导入的标头:
// defs.h struct Color { int red, green, blue; }; #define MAX_VALUE 255
// 演示迅捷 extension Color: CustomStringConvertible { // C结构的扩展 public var description: String { return "Color(red: \(red), green: \(green), blue: \(blue))" } } print("MAX_VALUE is: \(MAX_VALUE)") // C宏成为常量 let color = Color(red: 0xCA, green: 0xCA, blue: 0xD0) // C结构初始化器 print("The color is \(color)")
$ swiftcdemo.swift-import-objc-header defs.h && ./demo MAX_VALUE is: 255 The color is Color(red: 202, green: 202, blue: 208)