External symbols

Symbols from linked libraries can be declared as extern functions.

Koi follows the System V ABI and can seamlessly work with C code. Your program is also linked with libc by default:

extern func puts(s string)

func main() int {
    puts("Hello from libc!")
    return 0
}

Sometimes C libraries use strange or inconsistent naming conventions. The alias modifier will rename the symbol to whatever you want. It is purely semantic and does not change the compiled code in any way.

@alias stringCompare
extern func strcmp(a string, b string) int

func equal(a string, b string) bool {
    return stringCompare(a, b) == 0
}

External symbols can also be re-exported. Aliasing works with exports as well. The standard library io.println function is actually declared as:

@alias println
pub extern func puts(s string)