ternary-operator

问题 Just out of curiosity, asking this Like the expression one below a = (condition) ? x : y; // two outputs why can't we have an operator for enums? say, myValue = f ??? fnApple() : fnMango() : fnOrange(); // no. of outputs specified in the enum definition instead of switch statements (even though refactoring is possible) enum Fruit { apple, mango, orange }; Fruit f = Fruit.apple; Or is it some kind of useless operator? 回答1: I can't say I've ever wanted such an operator - which would be

问题 How would one shorten the following using ternary operators? if ((pos - maxPos) == (c.clientWidth)) { $j("#next").addClass("filter"); } else { $j("#next").removeClass("filter"); } 回答1: No need to use a ternary operator, .toggleClass() accepts a second argument to determine if the class should be added or removed: $j('#next').toggleClass('filter', ((pos - maxPos) == c.clientWidth)) However, for the sake of answering your question exactly like you asked (don't use it!): $j('#next')[((pos -

问题 Research project here. In my C++ library, I am including C files: #include "aprogram.c" which I execute symbolically by overloading (almost) all operators. I have to be able to detect (condition) ? this : that and extract condition , this and that for usage in my symbolic execution library. However, SO 1, SO 2 and SO 3 amongst others already helped me realise that ?: cannot be overloaded. Is there any way for me to forcibly overload ?: anyways? Can I change all ?: statements in my included C

问题 Here is my code: var now = DateTime.Now; var firstOfMonth = new DateTime(now.Year, now.Month, 1, 0, 0, 1); var objectsAfterFirstOfThisMonth= _context.DataObjects .Where(x => x.dateClosed == null ? x.dateClosed : x.dateCreated > firstOfMonth); I get the following compile error: There is no implicit conversion between 'System.Nullable' and 'bool' I don't understand the lambda syntax enough to understand this error. If I am unable to use this ternary syntax, then I will be required to get the

问题 I am having trouble understanding the concept of associativity in the context of ternary operators. In most cases, ternary operators look like this: a ? b : c In this case, no associativity is needed to evaluate the expression. Sometimes though, Ternary Operators are nested: a ? b : c ? d : e a ? b : (c ? d : e) // : is right-associative However, the nesting could also be inverted a ? b ? c : d : e a ? (b ? c : d) : e // : is left-associative What is the best way to explain this phenomenon?

问题 I need to print some string based on the true or false of a condition. For example: if(i == m) { Console.WriteLine("Number is valid"); } else { Console.WriteLine("Number is invalid"); } How can I check this condition and print a message using conditional operator and with only one Console.WriteLine ? I was trying: (i == m) ? Console.WriteLine("Number is valid") : Console.WriteLine("Number is not valid"); I know I'm doing it wrong here. Can someone please tell me the correct way? 回答1: Try this

问题 This question already has answers here : Closed 6 years ago . Possible Duplicate: PHP ternary operator not working as expected I dont know what is wrong with my code? My PHP Version is 5.4.7. $b = 'a'; $c = 'd'; echo $b == 'a' ? 2: $c == 'a' ? 1 : 0; output 1 right answer should be 2..... Thank you very much for your advice. 回答1: You need to add some parenthesis. $b = 'a'; $c = 'd'; echo ($b == 'a') ? 2 : ($c == 'a' ? 1 : 0); 来源： https://stackoverflow.com/questions/14399745/php-ternary

问题 I am implementing a language interpreter in C# using the DLR, and I'm having some troubles with the ternary operator. At this point, I have basic function declarations/calls implemented, like so: F := (x) -> x + 1 F(1) # returns 2 I've not had a problem with a function body being a sequence of expressions -- the value of the last expression is always returned, and I've made sure all cases in the interpreter return at least something as a side effect. I'm now trying to implement the ternary

问题 This question already has answers here : Kotlin Ternary Conditional Operator (28 answers) Closed 3 years ago . So in java we have the ternary operator (?), which sometimes is useful to easy some value computed by a if-else inlines. For example: myAdapter.setAdapterItems( textToSearch.length == 0 ? noteList : noteList.sublist(0, length-5) ) I know the equivalent in kotlin would be: myAdapter.setAdapterItems( if(textToSearch.length == 0) noteList else noteList.sublist(0, length-5) ) But i just

问题 Consider the following two alternatives of getting the higher number between currentPrice and 100 ... int price = currentPrice > 100 ? currentPrice : 100 int price = Math.Max(currentPrice, 100) I raised this question because I was thinking about a context where the currentPrice variable could be edited by other threads. In the first case... could price obtain a value lower than 100 ? I'm thinking about the following: if (currentPrice > 100) { //currentPrice is edited here. price =