void CheckLiteral()
{
switch (t.val) {
case "LL": t.kind = 20; break;
case "RR": t.kind = 21; break;
case "RRC": t.kind = 22; break;
case "LLC": t.kind = 23; break;
case "PORT": t.kind = 28; break;
case "IN": t.kind = 29; break;
case "OUT": t.kind = 30; break;
case "TRIG": t.kind = 33; break;
case "WIRE": t.kind = 34; break;
case "main": t.kind = 35; break;
default: break;
}
}