Node ParseMultiplyDivide()
{
var lhs = ParseUnary();
while (true)
{
Func <double, double, double> op = null;
if (_tokenizer.Token == Token.Multiply)
{
op = (a, b) => a * b;
}
else if (_tokenizer.Token == Token.Divide)
{
op = (a, b) => a / b;
}
if (op == null)
{
return(lhs);
}
_tokenizer.NextToken();
var rhs = ParseUnary();
lhs = new NodeBinary(lhs, rhs, op);
}
}
Node ParseAddSubtract()
{
var lhs = ParseMultiplyDivide();
while (true)
{
Func <double, double, double> op = null;
if (_tokenizer.Token == Token.Add)
{
op = (a, b) => a + b;
}
else if (_tokenizer.Token == Token.Subtract)
{
op = (a, b) => a - b;
}
if (op == null)
{
return(lhs); // no
}
_tokenizer.NextToken();
var rhs = ParseMultiplyDivide();
lhs = new NodeBinary(lhs, rhs, op);
}
}