vformat gives you the same functionality is format() but allows you to pass in parameters as an arbitrary length array.

vformat.nut

function vformat(fmt,...) {
    local args = [this,fmt];
    if (typeof(vargv[0]) == "array") {
        vargv = vargv[0];
    }
    args.extend(vargv);
    return format.acall(args);
}

// ----------------------[ Example use ]----------------------

function log(aformat, ...) {
    server.log(vformat(aformat, vargv));
}

log("%s, %s!", "Hello", "world");