public object visitUnaryExpr(Expr.UnaryExpr unaryExpr)
{
object right = evaluate(unaryExpr.right);
switch (unaryExpr.operatorToken.type)
{
case TokenType.EXCLAMATION:
return(!isTruthy(right));
case TokenType.MINUS:
checkNumberOperand(unaryExpr.operatorToken, right);
return(-(double)right);
case TokenType.MINUS_MINUS:
checkNumberOperand(unaryExpr.operatorToken, right);
return((double)right - 1.0);
case TokenType.PLUS_PLUS:
checkNumberOperand(unaryExpr.operatorToken, right);
return((double)right + 1.0);
}
return(null);
}
public object visitUnaryExpr(Expr.UnaryExpr unaryExpr)
{
resolve(unaryExpr.right);
return(null);
}
public string VisitUnaryExpr(Expr.UnaryExpr expr)
{
return(Parenthesize(expr.Operator.Lexeme, expr.Right));
}
public string visitUnaryExpr(Expr.UnaryExpr expr)
{
return(parenthesize(expr.operatorToken.lexeme, new Expr[] { expr.right }));
}
public object VisitUnaryExpr(Expr.UnaryExpr expr)
{
Resolve(expr.Right);
return(null);
}