public object visitExprUnaryExpr(ExprUnary expr)
{
object right = evaluate(expr.right);
switch (expr.eOperator.type)
{
case TokenType.MINUS:
checkNumberOperand(expr.eOperator, right);
return(-(double)right);
case TokenType.BANG:
return(!isTruthy(right));
default:
return(null);
}
}
public object visitExprUnaryExpr(ExprUnary expr)
{
resolve(expr.right);
return(null);
}
public object visitExprUnaryExpr(ExprUnary expr)
{
return(parenthesize(expr.eOperator.lexeme, expr.right));
}