Usually empty try-catch is a bad idea because you are silently swallowing an error condition and then continuing execution. Occasionally this may be the right thing to do, but often it’s a sign that a developer saw an exception, didn’t know what to do about it, and so used an empty catch to silence the … Read more
The way to preserve the stack trace is through the use of the throw; This is valid as well try { // something that bombs here } catch (Exception ex) { throw; } throw ex; is basically like throwing an exception from that point, so the stack trace would only go to where you are … Read more
You can trap unhandled exceptions at different levels: AppDomain.CurrentDomain.UnhandledException From all threads in the AppDomain. Dispatcher.UnhandledException From a single specific UI dispatcher thread. Application.Current.DispatcherUnhandledException From the main UI dispatcher thread in your WPF application. TaskScheduler.UnobservedTaskException from within each AppDomain that uses a task scheduler for asynchronous operations. You should consider what level you need to … Read more
Try turning on warnings in ghci. This enables the compile time warnings you can get with ghc by passing -W, for example. You can do this several ways: ghci -fwarn-incomplete-patterns Or Neil Mitchell describes how he sets this up in his .ghci. Here is the relevant excerpt: :set -fwarn-incomplete-patterns You can manually enter this at … Read more
Update: Joyent now has their own guide. The following information is more of a summary: Safely “throwing” errors Ideally we’d like to avoid uncaught errors as much as possible, as such, instead of literally throwing the error, we can instead safely “throw” the error using one of the following methods depending on our code architecture: … Read more
I’m not sure it adds much, but I got the expected Caused by using the variation of takteek’s answer shown below. I ran it from the command line to be sure the IDE wasn’t “helping”. $ java -cp build/classes TableWithExecutor StartShedule: PENDING -> STARTED java.util.concurrent.ExecutionException: java.lang.ArrayIndexOutOfBoundsException: Array index out of range: 2 at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:222) at … Read more
Yes, there is a difference; throw ex resets the stack trace (so your errors would appear to originate from HandleException) throw doesn’t – the original offender would be preserved. static void Main(string[] args) { try { Method2(); } catch (Exception ex) { Console.Write(ex.StackTrace.ToString()); Console.ReadKey(); } } private static void Method2() { try { Method1(); } … Read more
TL;DR: Use StandardError instead for general exception catching. When the original exception is re-raised (e.g. when rescuing to log the exception only), rescuing Exception is probably okay. Exception is the root of Ruby’s exception hierarchy, so when you rescue Exception you rescue from everything, including subclasses such as SyntaxError, LoadError, and Interrupt. Rescuing Interrupt prevents … Read more
Well then: welcome to the R world 😉 Here you go Setting up the code urls <- c( “http://stat.ethz.ch/R-manual/R-devel/library/base/html/connections.html”, “http://en.wikipedia.org/wiki/Xz”, “xxxxx” ) readUrl <- function(url) { out <- tryCatch( { # Just to highlight: if you want to use more than one # R expression in the “try” part then you’ll have to # use … Read more
This is a nasty problem induced by the wow64 emulation layer that allows 32-bit code to run on the 64-bit version of Windows 7. It swallows exceptions in the code that runs in response to a notification generated by the 64-bit window manager, like the Load event. Preventing the debugger from seeing it and stepping … Read more