throw

I picked this up in one of my brief forays to reddit: http://www.smallshire.org.uk/sufficientlysmall/2009/07/31/in-c-throw-is-an-expression/ Basically, the author points out that in C++: throw "error" is an expression. This is actually fairly clearly spelt out in the C++ Standard, both in the main text and the grammar. However, what is not clear (to me at least) is what is the type of the expression? I guessed " void ", but a bit of experimenting with g++ 4.4.0 and Comeau yielded this code: void f() { } struct S {}; int main() { int x = 1; const char * p1 = x == 1 ? "foo" : throw S(); // 1

Please find the code in the image below. 1. Assign the returned value of a function, which throws an error actually, to the variable 'withLet' that declared by using keyword 'let'. 2. call 'withLet', an error occured: 'withLet is not defined'. 3. try to assert 'withLet' using 'let', an error shows that 'withLet' has already been declared. But the paradox is not exist for 'var' (Please find in the following image). I'm curious about what caused the different behaviors between these two situations. It's quite wired that 'not defined' an 'already been declared' describe a same variable. let

I've been reading about unchecked versus checked questions, none of the online resources have been truly clear about the difference and when to use both. From what I understand, both of them get thrown at runtime, both of them represent program states that are outside the expected bounds of the logic, but checked exceptions must be explicitly caught while unchecked ones do not. My question is, suppose for argument's sake I have a method that divides two numbers double divide(double numerator, double denominator) { return numerator / denominator; } and a method that requires divison somewhere

Conventional wisdom says you can only throw objects that extend Throwable in Java, but is it possible to disable the bytecode verifier and get Java to compile and run code that throws arbitrary objects - or even primitives? I looked up the JVM's athrow and it will pop the first objref on the operand stack; but would it check if said reference points to a Throwable at run time? John Kugelman It depends on your JVM implementation. According to the Java VM specification it is undefined behavior if the object is not Throwable . The objectref must be of type reference and must refer to an object

I have been coding in Java for a while now. But sometimes, I don't understand when I should throw the exception and when should I catch the exception. I am working on a project in which there are lot of methods. The hierarchy is something like this- Method A will call Method B and Method B will call some Method C and Method C will call Method D and Method E. So currently what I am doing is- I am throwing exceptions in all the methods and catching it in Method A and then logging as an error. But I am not sure whether this will be the right way to do it? Or should I start catching exceptions in

Why do the following lines of code not create a compiler warning? void Main() { throw new Exception(); throw new Exception(); } As I see it, the compiler should inform you that the second throw exception cannot be reached. It is clearly a compiler bug, and it was introduced in C# 3.0 -- right around the time that I heavily refactored the reachability checker. This is probably my bad, sorry. The bug is completely benign; basically, we just forgot a case in the warning reporter. We generate the reachability information correctly; as others have noted, we correctly trim out the unreachable code

This question already has an answer here: Exception handling : throw, throws and Throwable 8 answers Can any one clearly state the difference between throw and throws in Java exception handling with an example? I have tried googling but couldn't arrive at a conclusion. Pls help Nirav Prajapati throws clause is used to declare an exception and throw keyword is used to throw an exception explicitly. If we see syntax wise then throw is followed by an instance variable and throws is followed by exception class names. The keyword throw is used inside method body to invoke an exception and throws