function foo() {
  return a, b;
}
if (a, b, c) d();
throw a, b, c;
switch (a, b, c) {}
for (a in b, c);
for (a of (b = c, d));
while (a, b, c);
!function () {}(), a();
a, b, c;
a, b, c;
a`${1, 2}`;
(a, b)`${1, 2}`;
`${1, 2}`;
export default (c, d);