conditional-operator

Which operator is faster: ?: or &&

While developing ASP.NET applications I often need to parse a boolean value given in string form, e.g. from a query string like ?visible=true I found two solutions to implement the parsing: bool Visible { get { bool b; return Boolean.TryParse(this.Request["visible"], out b) && b; } } or bool Visible { ...

Ternary operators and Return in C

Why can't we use return keyword inside ternary operators in C, like this: sum > 0 ? return 1 : return 0; ...

Weird behaviour with conditional operator in .Net

This has me pretty stumped. Maybe I'm too tired right now. Rectangle rectangle = new Rectangle(0, 0, image.Width, image.Height); Rectangle cropArea = inputArea == null ? rectangle : inputArea.Value; if (inputArea == null) cropArea = rectangle; inputArea is a nullable Rectangle, which in my particular case is null....

Full if/else statement vs. Conditional Operator

Possible Duplicates: Benefits of using the conditional ?: (ternary) operator Is the conditional operator slow? Hi all, I've got a pretty simple question regarding the different if/else statements. Apart from writing less code, are there any other benefits for using the conditional operator as opposed to the full if/else st...

Assigning and Conditional Testing Simultaneously in C++

I have three functions that return integer error codes, e.g. int my_function_1(const int my_int_param); int my_function_2(const int my_int_param); int my_function_3(const int my_int_param); I want to assign and test for error at the same time for brevity. Will the following work and be portable? int error=0; ... if ( error || (...

Ternary Operator

Why compiler cannot specialize this function and is there a way to force him to do so? The error I'm getting: Error 1 error C2893: Failed to specialize function template ''unknown-type' Ternary::check(bool,Left,Right)' #include "stdafx.h" #include <iostream> #include <string> using std::cout; using std::string; template<int v> stru...

C# Allow user to enter conditional rules

Hello. I write code in isolation, that is I work for myself. I need some advice on how you might implement the following functionality or if there are some tools that already exist to help make this task easier to accomplish. I have a scenario (C# application) in which I would like the user to be able to enter conditional rules which wi...

Booleans, conditional operators and autoboxing

Why does this throw NPE public static void main(String[] args) throws Exception { Boolean b = true ? returnsNull() : false; // NPE on this line. System.out.println(b); } public static Boolean returnsNull() { return null; } while this doesn't public static void main(String[] args) throws Exception { Boolean b = true ?...

Jsp and ?: not working as expected

I have this code: <c:forEach var="product" items="${products}" begin="${begin}" end="${end}" varStatus="loopStatus" step="1"> <div class="home_app "${loopStatus.index % 2 == 0 ? '' : 'white_bg'}"> When I browse to the jsp I am getting this in the div: <div }="" white_bg="" :="" ?="" 0="" 2="=" %="" ${loopstatus.index="" class="ho...

Using the conditional operator ? to check for null session variable

Take a look at this code: System.Web.SessionState.HttpSessionState ss = HttpContext.Current.Session["pdfDocument"] ?? false; if ((Boolean)ss) { Label1.Text = (String)Session["docName"]; } Basically I want to check if HttpContext.Current.Session["pdfDocument"] is not null, and if it isn't to cast to...

Conditional Count of changes over time?

Hi all, I´d like to count the number of changes of binary factor variable. This variable can change from time to time back and forth multiple times for every user id. Now I´d like to count he number of changes per user id to this variable over a given timespan. The data is sorted by id,year,month,myfactor. I tried this in MySQL but ha...