Initial data commit

Task/Call-a-foreign-language-function/Hare/call-a-foreign-language-function.hare

@@ -0,0 +1,16 @@
+// hare run -lc ffi.ha
+
+use fmt;
+use strings;
+
+@symbol("strdup") fn cstrdup(_: *const char) *char;
+@symbol("free") fn cfree(_: nullable *void) void;
+
+export fn main() void = {
+	let s = strings::to_c("Hello, World!");
+	defer free(s);
+
+	let dup = cstrdup(s);
+	fmt::printfln("{}", strings::fromc(dup))!;
+	cfree(dup);
+};