exception – Page 3

throw Error(‘msg’) vs throw new Error(‘msg’)

May 28, 2022 by IT Nursery

var err1 = Error(‘message’); var err2 = new Error(‘message’); What’s the difference? Looking at them in the chrome console, they look identical. Same properties on the object and the same __proto__ chain. Almost seems like Error acts like a factory. Which one is correct and why? 2 Answers 2

Throw keyword in function’s signature

May 28, 2022 by IT Nursery

What is the technical reason why it is considered bad practice to use the C++ throw keyword in a function signature? bool some_func() throw(myExc) { … if (problem_occurred) { throw myExc(“problem occurred”); } … } 7 Answers 7

How do I raise the same Exception with a custom message in Python?

May 28, 2022 by IT Nursery

I have this try block in my code: try: do_something_that_might_raise_an_exception() except ValueError as err: errmsg = ‘My custom error message.’ raise ValueError(errmsg) Strictly speaking, I am actually raising another ValueError, not the ValueError thrown by do_something…(), which is referred to as err in this case. How do I attach a custom message to err? I … Read more

How do I catch a numpy warning like it’s an exception (not just for testing)?

May 27, 2022 by IT Nursery

I have to make a Lagrange polynomial in Python for a project I’m doing. I’m doing a barycentric style one to avoid using an explicit for-loop as opposed to a Newton’s divided difference style one. The problem I have is that I need to catch a division by zero, but Python (or maybe numpy) just … Read more

Exception thrown inside catch block – will it be caught again?

May 26, 2022 by IT Nursery

This may seem like a programming 101 question and I had thought I knew the answer but now find myself needing to double check. In this piece of code below, will the exception thrown in the first catch block then be caught by the general Exception catch block below? try { // Do something } … Read more

Flutter: Unhandled Exception: ServicesBinding.defaultBinaryMessenger was accessed before the binding was initialized

May 25, 2022 by IT Nursery

Any solution to solve this problem? Stacktrace: [VERBOSE-2:ui_dart_state.cc(148)] Unhandled Exception: ServicesBinding.defaultBinaryMessenger was accessed before the binding was initialized. If you’re running an application and need to access the binary messenger before `runApp()` has been called (for example, during plugin initialization), then you need to explicitly call the `WidgetsFlutterBinding.ensureInitialized()` first. If you’re running a test, you … Read more

django MultiValueDictKeyError error, how do I deal with it

May 25, 2022 by IT Nursery

I’m trying to save a object to my database, but it’s throwing a MultiValueDictKeyError error. The problems lies within the form, the is_private is represented by a checkbox. If the check box is NOT selected, obviously nothing is passed. This is where the error gets chucked. How do I properly deal with this exception, and … Read more

Handling exceptions from Java ExecutorService tasks

May 25, 2022 by IT Nursery

I’m trying to use Java’s ThreadPoolExecutor class to run a large number of heavy weight tasks with a fixed number of threads. Each of the tasks has many places during which it may fail due to exceptions. I’ve subclassed ThreadPoolExecutor and I’ve overridden the afterExecute method which is supposed to provide any uncaught exceptions encountered … Read more

Can constructors throw exceptions in Java?

May 25, 2022 by IT Nursery

Are constructors allowed to throw exceptions? 6 Answers 6