Swift Language Working with C and Objective-C Specify a bridging header to swiftc
Example
The -import-objc-header flag specifies a header for swiftc to import:
// defs.h
struct Color {
int red, green, blue;
};
#define MAX_VALUE 255
// demo.swift
extension Color: CustomStringConvertible { // extension on a C struct
public var description: String {
return "Color(red: \(red), green: \(green), blue: \(blue))"
}
}
print("MAX_VALUE is: \(MAX_VALUE)") // C macro becomes a constant
let color = Color(red: 0xCA, green: 0xCA, blue: 0xD0) // C struct initializer
print("The color is \(color)")
$ swiftc demo.swift -import-objc-header defs.h && ./demo MAX_VALUE is: 255 The color is Color(red: 202, green: 202, blue: 208)
