Questions related to handling errors and exceptions. According to Wikipedia, Exception handling is the process of responding to the occurrence, during computation, of exceptions – anomalous or exceptional events requiring special processing – often changing the normal flow of program execution. It ...

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98
votes
11answers
18k views

The modern way to perform error handling…

I've been pondering this problem for a while now and find myself continually finding caveats and contradictions, so I'm hoping someone can produce a conclusion to the following: Favour exceptions ...
84
votes
12answers
7k views

How big does my project need to be for me to unit test it? [closed]

I assume that my project is decoupled enough to allow for unit testing. But how big, exactly, in terms of clases and functions does my project need to be to make unit testing worthwhile? We all make ...
82
votes
14answers
43k views

Why is 0 false?

This question may sound dumb, but why does 0 evaluates to false and any other [integer] value to true is most of programming languages? String comparison Since the question seems a little bit too ...
82
votes
16answers
24k views

Should one check for null if he does not expect null?

Last week, we had a heated argument about handling nulls in our application's service layer. The question is in the .NET context, but it will be the same in Java and many other technologies. The ...
68
votes
12answers
8k views

I've been told that Exceptions should only be used in exceptional cases. How do I know if my case is exceptional?

My specific case here is that the user can pass in a string into the application, the application parses it and assigns it to structured objects. Sometimes the user may type in something invalid. ...
57
votes
16answers
25k views

How to handle divide by zero in a language that doesn't support exceptions?

I'm in the middle of developing a new programming language to solve some business requirements, and this language is targeted at novice users. So there is no support for exception handling in the ...
53
votes
5answers
7k views

Will a computer attempt to divide by zero?

We all know 0/0 is Undefined and returns an error if I were to put it into a calculator, and if I were to create a program (in C at least) the OS would terminate it when I try to divide by zero. But ...
52
votes
7answers
4k views

Should one check for every little error in C? [duplicate]

As a good programmer one should write robust codes that will handle every single outcome of his program. However, almost all functions from the C library will return 0 or -1 or NULL when there's an ...
50
votes
8answers
21k views

Return magic value, throw exception or return false on failure?

I sometimes end up having to write a method or property for a class library for which it is not exceptional to have no real answer, but a failure. Something cannot be determined, is not available, not ...
44
votes
6answers
4k views

How safe are hidden AJAX requests that fake performance?

What is a hidden AJAX request? I've noticed an increase in the usage of hidden AJAX requests designed to make a user's action appear to happen immediately. I'll refer to this type of AJAX request as ...
43
votes
2answers
20k views

What are the definitive guidelines for custom Error Handling in ASP.NET MVC 3?

The process of doing custom error handling in ASP.NET MVC (3 in this case) seems to be incredibly neglected. I've read through the various questions and answers here, on the web, help pages for ...
41
votes
10answers
4k views

Why are exceptions considered better than explicit error testing? [duplicate]

Possible Duplicate: Defensive Programming vs Exception Handling? if/else statements or exceptions I often come across heated blog posts where the author uses the argument: "exceptions vs ...
38
votes
6answers
41k views

try-catch in javascript… isn't it a good practice?

There is a provision for try-catch block in javascript. While in java or any other language it is mandatory to have error handling, I don't see anybody using them in javascript for greater extent. ...
35
votes
7answers
7k views

Should a stack trace be in the error message presented to the user?

I've got a bit of an argument at my workplace and I'm trying to figure out who is right, and what is the right thing to do. Context: an intranet web application that our customers use for accounting ...
35
votes
7answers
4k views

Arguments against error suppression

I've found a piece of code like this in one of our projects: SomeClass QueryServer(string args) { try { return SomeClass.Parse(_server.Query(args)); } ...
32
votes
3answers
5k views

Is address 0000000C a special address?

When programming sometimes things break. You made a mistake and your program tries to read from a wrong address. One thing that stands out to me that often those exceptions are like : Access ...
31
votes
4answers
2k views

How much information about an error should be shown to the user?

Applications can always throw errors. If such an error occurs, the user should be notified, because what he asked the application to do has not succeeded. However, how much information should the ...
30
votes
20answers
3k views

How do you tackle really bizarre errors that keep you puzzled for more than 10 hours? [closed]

You know them, those errors that make NO sense. Where it seems like a gremlin just jumped deep inside your chips and messed up something. Do you take a walk, write stuff, call an uncle?
30
votes
9answers
2k views

Is possible to write too many asserts?

I am a big fan of writing assert checks in C++ code as a way to catch cases during development that cannot possibly happen but do happen because of logic bugs in my program. This is a good practice in ...
28
votes
7answers
1k views

Is it okay to use exceptions as tools to “catch” errors early?

I use exceptions to catch problems early. For example: public int getAverageAge(Person p1, Person p2){ if(p1 == null || p2 == null) throw new IllegalArgumentException("One or more of ...
26
votes
3answers
1k views

Should I use HTTP status codes to describe application level events

Several servers I have dealt with will return HTTP 200 for requests that the client ought to consider a failure, with something like 'success : false' in the body. This does not seem like a proper ...
23
votes
15answers
15k views

Arguments for or against using Try/Catch as logical operators [closed]

I just discovered some lovely code in our companies app that uses Try-Catch blocks as logical operators. Meaning, "do some code, if that throws this error, do this code, but if that throws this error ...
17
votes
5answers
8k views

null pointers vs. Null Object Pattern

Attribution: This grew out of a related P.SE question My background is in C / C++, but I have worked a fair amount in Java and am currently coding C#. Because of my C background, checking passed and ...
17
votes
2answers
1k views

Cleanest way to report errors in Haskell

I'm working on learning Haskell, and I've come across three different ways of dealing with errors in functions I write: I can simply write error "Some error message.", which throws an exception. I ...
12
votes
3answers
8k views

Handling Errors In PHP When Using MVC

I've been using Codeigniter a lot recently, but one thing that gets on my nerves is handling errors and displaying them to the user. I've never been good at handling errors without it getting messy. ...
11
votes
4answers
4k views

`trigger_error` vs `throw Exception` in the context of PHP's magic methods

I'm having a debate with a colleague over the correct usage (if any) of trigger_error in the context of magic methods. Firstly, I think that trigger_error should be avoided except for this one case. ...
10
votes
6answers
1k views

Designing database related methods, which is better to return: true/false or row affected?

I have some methods that perform some data changing in a database (insert, update, and delete). The ORM I'm using return row-affected int values for those type of method. What should I return for "my ...
10
votes
3answers
1k views

Recommend a design pattern/approach to exposing/tolerating/recovering from system errors, Exception handling (e.g.s in Java, C++, Perl, PHP)

Can you recommend a design pattern/approach to exposing/tolerating/recovering from system errors, Exception handling (Java, C++, Perl, PHP)? Some errors need to be reported. Some errors can be ...
10
votes
4answers
1k views

Is error suppressing bad practice?

On a SO question I asked here about some code I was unsure about, someone replied "BTW, horrible code there: it uses the error suppressing symbol (@) a lot." Is there a reason why this is bad ...
10
votes
5answers
314 views

Is indiscriminately catching exceptions (Pokemon exception handling) ever acceptable? [duplicate]

Normally, I don't anticipate exceptions and if I get them, its something that I can't fix in my code - bad user input or connectivity issues with the database. But errors do occur so at the very ...
10
votes
3answers
2k views

Exceptions or Error codes

We are building a web service(SOAP, .Net) which would be talking to (mostly) native clients (windows, C++) and we are wondering what is the best way to communicate errors to the client (e.g. ...
10
votes
3answers
2k views

Different callbacks for error or error as first argument?

We (and the JS SO chat room) had a talk with @rlemon some days ago about his Little-XHR library about error handling. Basically, we wanted to decide which error handling pattern should be used: ...
9
votes
8answers
2k views

Using a try-finally (without catch) vs enum-state validation

I have been reading the advice on this question about how an exception should be dealt with as close to where it is raised as possible. My dilemma on the best practice is whether one should use a ...
8
votes
3answers
2k views

Page Not Found: 404 - the best content to put in this page [closed]

Do you let me know what kind of content I should put in the error-page like "404 page not found"? Example: "Unfortunately an error has occurred during the processing of your page request." "Page ...
8
votes
2answers
707 views

How should I handle logger failures?

In several of our company's applications, we use a custom logger. It's fairly robust, though we may replace it with something like NLog in the future. One of the logger's tasks is to log any ...
8
votes
2answers
2k views

What's the difference between robustness and fault-tolerance?

Systems / programs / distributed algorithms / ... are often described with the predicate robust or fault-tolerant. What is the difference? Details: When I google for +robust +"fault-tolerant", I ...
8
votes
2answers
1k views

How to Implement Error Handling [closed]

Even though I've programmed on a professional level for some years I still do not fully understand error handling. Although my applications work fine, the error handling isn't implemented at a ...
8
votes
2answers
417 views

Is the strong exception safety guarantee with a pass-by-value argument which can throw on destruction possible?

Suppose you have a type with a throwing destructor, and a function receiving it by value. Can that operation ever provide anything better than the basic exception guarantee? Or formulated differently, ...
8
votes
2answers
236 views

Do we need to validate entire module usage or just arguments of public methods?

I've heard that it is recommended to validate arguments of public methods: Should one check for null if he does not expect null? Should a method validate its parameters? MSDN - CA1062: Validate ...
7
votes
4answers
1k views

Best Practice: Should error messages be handled by the API or by the App?

I am designing an application that interacts with a RESTful API. When returning error messages like Unable to sign up user Should the error message be generated by the app? or by the API? I am ...
7
votes
2answers
123 views

How to work with/around an API that does not return errors?

I am currently working on a project which requires data fetching from a 3rd party closed API (over SOAP). Currently I'm in a situation where I have to do argument and data validation inside our ...
7
votes
2answers
339 views

What's the best way to handle Windows API errors in response to system messages or when I have nowhere to return them to?

This is going to be a really stupid question and I hope it's fine for Stack Exchange at all, let alone just this part of it... Right now, my custom Table control uses panic() functions that print an ...
6
votes
5answers
931 views

Checked vs Unchecked vs No Exception… A best practice of contrary beliefs

There are many requirements needed for a system to properly convey and handle exceptions. There are also many options for a language to choose from to implement the concept. Requirements for ...
6
votes
2answers
661 views

Designing exception classes

I'm coding a small library and I'm having some trouble with designing the exception handling. I must say that I am (still) confused by this feature of the C++ language and I tried to read as much as ...
6
votes
3answers
275 views

When you write wrappers for APIs how do you handle usage errors?

When you write wrappers for APIs how do you handle usage errors? Do you assume that the user uses it right and write the wrapper such that it makes the call to the server and let the server return ...
5
votes
5answers
3k views

How should I handle exception that *should* never be thrown? [duplicate]

What is the best way to handle errors that shouldn't ever happen? My current way to do this is to throw an exception if the 'thing that shouldn't happen' does happen, like so: /* * Restoring from a ...
5
votes
3answers
11k views

Best Practices To Create Error Codes Pattern For an Enterprise Project in C# [closed]

I'm working on an enterprise project which will be deployed in many SMBs and Enterprises. The support for this project would be struggling and so I want to create a coding pattern for errors (Like ...
5
votes
3answers
3k views

Authoritative sources for exception handling best practices [closed]

My work place suffers from a bad case of the Pokemon Exception Handling anti-pattern with constructs like the following splattered across the code base: try { ... } catch (Exception ex) { // ...
5
votes
2answers
265 views

Is error suppression acceptable in role of logic mechanism?

This came up in code review at work in context of PHP and @ operator. However I want to try keep this in more generic form, since few question about it I found on SO got bogged down in technical ...
5
votes
2answers
809 views

Should I always return an error code from C functions?

I have the following code in many places in a large application: if (datastruct.data_ok && cur_time > datastruct.start_time && cur_time < datastruct.end_time) { ...