protected dynamic Visit(AST node)
{
return(node switch
{
Program program => VisitProgram(program),
Block block => VisitBlock(block),
VarDecl decl => VisitDecl(decl),
Compound compound => VisitCompound(compound),
Assign assign => VisitAssign(assign),
NoOp noOp => VisitNoOp(noOp),
Var var => VisitVar(var),
Num num => VisitNum(num),
BinOp binOp => VisitBinOp(binOp),
UnaryOp unaryOp => VisitUnaryOp(unaryOp),
_ => throw new NotImplementedException()
});
internal AST Expr()
{
var result = Term();
while (currentToken.Type == Operation.Plus || currentToken.Type == Operation.Minus)
{
if (currentToken.Type == Operation.Plus)
{
Eat(Operation.Plus);
result = new BinOp(result, Operation.Plus, Term());
}
else if (currentToken.Type == Operation.Minus)
{
Eat(Operation.Minus);
result = new BinOp(result, Operation.Minus, Term());
}
else
{
throw new InvalidOperationException();
}
}
return(result);
}
internal AST Term()
{
var result = Factor();
while (currentToken.Type == Operation.Mul || currentToken.Type == Operation.FloatDiv || currentToken.Type == Operation.IntegerDiv)
{
if (currentToken.Type == Operation.Mul)
{
Eat(Operation.Mul);
result = new BinOp(result, Operation.Mul, Factor());
}
else if (currentToken.Type == Operation.FloatDiv)
{
Eat(Operation.FloatDiv);
result = new BinOp(result, Operation.FloatDiv, Factor());
}
else if (currentToken.Type == Operation.IntegerDiv)
{
Eat(Operation.IntegerDiv);
result = new BinOp(result, Operation.IntegerDiv, Factor());
}
}
return(result);
}