function f() {
    return (x)=>x;
}
function f2() {
    return (x)=>x;
}
function f3() {
    return (x)=>x;
}
(function() {
    return (v)=>v;
});
(function() {
    return (v)=>v;
});
(function*() {
    yield (v)=>v;
});
(function*() {
    throw (v)=>v;
});
