async function () { statements }
async function (param1) { statements }
async function (param1, param2) { statements }
...
async function (param1, param2, ..., paramN) { statements }
async function name() { statements }
async function name(param1) { statements }
async function name(param1, param2) { statements }
...
async function name(param1, param2, ..., paramN) { statements }