public Node UnaryExpression()
{
if (CurrentToken == TokenCategory.NOT)
{
var result = new Not()
{
AnchorToken = Expect(TokenCategory.NOT)
};
result.Add(UnaryExpression());
return(result);
}
else if (CurrentToken == TokenCategory.NEG)
{
var result = new Neg()
{
AnchorToken = Expect(TokenCategory.NEG)
};
result.Add(UnaryExpression());
return(result);
}
else
{
return(SimpleExpression());
}
}
public Node SimpleExpr()
{
switch (Current)
{
case TokenCategory.PAR_OPEN:
Expect(TokenCategory.PAR_OPEN);
var n = Expr();
Expect(TokenCategory.PAR_CLOSE);
return(n);
case TokenCategory.NOT:
var node1 = new Not()
{
AnchorToken = Expect(TokenCategory.NOT)
};
node1.Add(SimpleExpr());
return(node1);
case TokenCategory.LITERAL_0:
return(new Literal_0()
{
AnchorToken = Expect(TokenCategory.LITERAL_0)
});
case TokenCategory.LITERAL_1:
return(new Literal_1()
{
AnchorToken = Expect(TokenCategory.LITERAL_1)
});
default:
throw new SyntaxError();
}
}
//expr-unary>//
public Node ExprUnary()
{
var xprUn = new Node();
if (firstofUnary.Contains(CurrentToken))
{
while (firstofUnary.Contains(CurrentToken))
{
switch (CurrentToken)
{
case TokenCategory.NOT:
xprUn = new Not()
{
AnchorToken = Expect(TokenCategory.NOT)
};
break;
default:
throw new SyntaxError(firstofUnary,
tokenStream.Current);
}
xprUn.Add(ExprUnary());
}
}
else
{
xprUn = ExprPrimary();
}
return(xprUn);
}
public Node UnaryExpression()
{
if (CurrentToken == TokenCategory.NOT)
{
var result = new Not()
{
AnchorToken = Expect(TokenCategory.NOT)
};
result.Add(UnaryExpression());
return(result);
}
else if (CurrentToken == TokenCategory.MINUS)
{
var result = new Negative()
{
AnchorToken = Expect(TokenCategory.MINUS)
};
result.Add(UnaryExpression());
return(result);
}
else if (firstOfSimpleExpression.Contains(CurrentToken))
{
return(SimpleExpression());
}
else
{
throw new SyntaxError(firstOfUnaryExpression, tokenStream.Current);
}
}