The Weird and The Wonderful

   

The Weird and The Wonderful forum is a place to post Coding Horrors, Worst Practices, and the occasional flash of brilliance.

We all come across code that simply boggles the mind. Lazy kludges, embarrassing mistakes, horrid workarounds and developers just not quite getting it. And then somedays we come across - or write - the truly sublime.

Post your Best, your worst, and your most interesting. But please - no programming questions . This forum is purely for amusement and discussions on code snippets. All actual programming questions will be removed.

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Re: What this 'null' check doing here... Mark Starr16-Jul-13 5:20 Mark Starr 16-Jul-13 5:20  Not a prob, I was in fact, just starting the day, and clearly had too little coffee in my system to type, much less proof. We had just been playing around with javascript to see what happens when you don't declare a variable versus when you declare it and don't assign a value - how it affects checking for undefined, not-undefined, null, etc. And, Yes, I typically write a lot more in T-SQL, but I also use VB, VB.NET, et al in my daily work - hence my disclaimer about not writing a lot of C#. I'm always careful when checking for nulls, so when I see comparison operator my hair stands up a bit. Initially, to me, the code looked as though someone had somehow had a bad experience populating the list from using the "new List<employee>();" call, and so put in a safety-catch (if you will) to try again if necessary. Or, perhaps, the second part was already there, and someone later came along and added the first line... I'm sure they though it was right at the time. Who knows! Thanks for the note KP. Cheers and happy coding, Mark Re: What this 'null' check doing here... GrumpyPants10-Jul-13 5:33 GrumpyPants 10-Jul-13 5:33  Check your version control. It's possible declaration and/or the assignment at declaration was added later. If an earlier version of the method had the List<employee> passed as a parameter, then the test for non-null would make sense. Re: What this 'null' check doing here... Mohammed Hameed10-Jul-13 19:35 Mohammed Hameed 10-Jul-13 19:35  Quote: It's possible declaration and/or the assignment at declaration was added later. Ok but in the case if it is added later also, the guy should have removed the null check as it is not applicable now. Anyhow that wasn't the case, I checked the source control Previous -> Read "CLR via C#" by Jeffrey Ritcher. Current -> Exploring WCF thru Apress' "Pro WCF" by Chris Peiris and Dennis Mulder. Next -> Need to read "The Art of Computer Programming" by Donald E. Knuth. Re: What this 'null' check doing here... RafagaX10-Jul-13 5:43 RafagaX 10-Jul-13 5:43  I bet the person who wrote this comes from a C/C++ background, there, you have to check for null every time or you may blow out something... CEO at: - Rafaga Systems - Para Facturas - Modern Components for the moment... Re: What this 'null' check doing here... Mohammed Hameed10-Jul-13 19:43 Mohammed Hameed 10-Jul-13 19:43  Correct. *** You're superb,,, What a guess!!! *** Previous -> Read "CLR via C#" by Jeffrey Ritcher. Current -> Exploring WCF thru Apress' "Pro WCF" by Chris Peiris and Dennis Mulder. Next -> Need to read "The Art of Computer Programming" by Donald E. Knuth. Re: What this 'null' check doing here... Michael Losinski10-Jul-13 5:59 Michael Losinski 10-Jul-13 5:59  The only thing that I can think of is technically new doesn't guarantee that the variable initialization will take place. In programming languages like c++ it could return null. This could happen if the memory was so fragmented that the allocation failed. However, instead of returning null in C# I believe it throws a out of memory exception. I have only seen this done in system critical embedded systems. Re: What this 'null' check doing here... Mohammed Hameed10-Jul-13 19:45 Mohammed Hameed 10-Jul-13 19:45  Thanks Michael. That was a excellent explanation. Previous -> Read "CLR via C#" by Jeffrey Ritcher. Current -> Exploring WCF thru Apress' "Pro WCF" by Chris Peiris and Dennis Mulder. Next -> Need to read "The Art of Computer Programming" by Donald E. Knuth. Re: What this 'null' check doing here... KP Lee10-Jul-13 21:01 KP Lee 10-Jul-13 21:01  Michael Losinski wrote: The only thing that I can think of is technically new doesn't guarantee that the variable initialization will take place. Who cares? If the "if" check returns true, the result of calling the routine could make it null. If it's mission critical, initialize it by calling the function and then throw it when the function sets it to null. (Which it doesn't seem to check for, when that is a very possible result of calling the function.) If you are so constrained by memory the new would fail, it'd fail in the function too, thereby throwing an error the code doesn't check for(catch). Re: What this 'null' check doing here... Michael Losinski11-Jul-13 3:40 Michael Losinski 11-Jul-13 3:40  Yes you could the code down to one line of code. You could catch the exception somewhere else, so I suppose the question could then become what do you do in a mission critical system when outofmemory exception or an allocation fails, therefore allowing you to gracefully shutdown. First thing that comes to mind is if the current thread is not mission critical you can kill that can free up some memory. Second, you could have a fail-safe that would allow you to kill all non-mission critical threads thus freeing memory. With the right permissions you could also kill the other applications. I've never implemented one but you could also have a "memory para-shoot" that at the start of the program allocates a chunk of memory and frees it when needed. I suppose allot of it depend on the system and requirements. Re: What this 'null' check doing here... Nilesh Shahane10-Jul-13 8:07 Nilesh Shahane 10-Jul-13 8:07  He is just double checking. Re: What this 'null' check doing here... Mohammed Hameed10-Jul-13 19:47 Mohammed Hameed 10-Jul-13 19:47  The same thing I told him when I saw this first time. Previous -> Read "CLR via C#" by Jeffrey Ritcher. Current -> Exploring WCF thru Apress' "Pro WCF" by Chris Peiris and Dennis Mulder. Next -> Need to read "The Art of Computer Programming" by Donald E. Knuth. Re: What this 'null' check doing here... MainFrameMan_ALIVE_AND_WELL$$10-Jul-13 10:03 MainFrameMan_ALIVE_AND_WELL$$ 10-Jul-13 10:03  Looks like a newbie whose prof in 101 programming hammered down checking objects before using them. This would be sensible if it were a thousand lines down in the code, but, if it is null where is the property/method to new it up? Re: What this 'null' check doing here... Mohammed Hameed10-Jul-13 19:48 Mohammed Hameed 10-Jul-13 19:48  Well, he is 4 yrs exp..... Previous -> Read "CLR via C#" by Jeffrey Ritcher. Current -> Exploring WCF thru Apress' "Pro WCF" by Chris Peiris and Dennis Mulder. Next -> Need to read "The Art of Computer Programming" by Donald E. Knuth. Re: What this 'null' check doing here... KP Lee10-Jul-13 21:13 KP Lee 10-Jul-13 21:13  Mohammed Hameed wrote: Well, he is 4 yrs exp.... So, he IS inexperienced! (I started coding in '74. Late start, '05 on C#.) Re: What this 'null' check doing here... Mohammed Hameed10-Jul-13 21:15 Mohammed Hameed 10-Jul-13 21:15  Ohh, is that? Previous -> Read "CLR via C#" by Jeffrey Ritcher. Current -> Exploring WCF thru Apress' "Pro WCF" by Chris Peiris and Dennis Mulder. Next -> Need to read "The Art of Computer Programming" by Donald E. Knuth. Re: What this 'null' check doing here... DarkChuky CR12-Jul-13 12:56 DarkChuky CR 12-Jul-13 12:56  it could make sense if it was a code update... let say it was like: XML List<Employee> employees = GetEmployessFromSucursal(sucursalID); if (employees != null){ employees = GetEmployees();//Get employes from other source } then for some reason the code was updated or copy&paste... there is also a proba that the IF used to have some other parameter and an ELSE... so again code that was not finally updated to the best final form. Re: What this 'null' check doing here... Mohammed Hameed14-Jul-13 19:46 Mohammed Hameed 14-Jul-13 19:46  Thanks. My Reading-o-Meter Previous -> Read "CLR via C#" by Jeffrey Richter. Current -> Exploring WCF thru Apress' "Pro WCF" by Chris Peiris and Dennis Mulder. Next -> Need to read "The Art of Computer Programming" by Donald E. Knuth. My blog - My recent article Re: What this 'null' check doing here... Chad3F13-Jul-13 19:17 Chad3F 13-Jul-13 19:17  Now a smart compiler should probably want about this. Something like when comparing signed and unsigned int's in C and it warns that the statement is always true (or false) due to conversion rules. Seems like maybe (I know.. "maybe?!?!") a programmer that didn't know what they're doing. That you have to first "create" the list, so you can "fill it in" with the GetEmployees() values or something. Along the same lines as novice programmers that create and assign a local number (or string) variable with a constant value because the function was prototyped with that data type, rather than pass the same constant number inline to the call. Could be worse.. I've seen this in [employed to write] software: C++ #define ZERO 0 #define ONE 1 #define TWO 2 Re: What this 'null' check doing here... Mohammed Hameed14-Jul-13 19:45 Mohammed Hameed 14-Jul-13 19:45  Thanks. My Reading-o-Meter Previous -> Read "CLR via C#" by Jeffrey Richter. Current -> Exploring WCF thru Apress' "Pro WCF" by Chris Peiris and Dennis Mulder. Next -> Need to read "The Art of Computer Programming" by Donald E. Knuth. My blog - My recent article Re: What this 'null' check doing here... Chad3F14-Jul-13 19:55 Chad3F 14-Jul-13 19:55  Just noticed a typo I made.. It should have said: "Now a smart compiler should probably warn about this." I guess spell check doesn't catch everything. More mining from our deep seam of WTF's Rob Grainger1-Jul-13 3:17 Rob Grainger 1-Jul-13 3:17  Another gem from the VB6 app I'm in the process of replacing. In production code no less. VB SQL = "select policyid, policynumber, covdate" ' Rest of SQL omitted MsgBox SQL RS.Open SQL, con, adOpenStatic My guess is this was a diagnostic message someone neglected to remove. The SQL statement is quite long (involving a few joins). Must be quite intimidating for users. "If you don't fail at least 90 percent of the time, you're not aiming high enough." Alan Kay. Re: More mining from our deep seam of WTF's jim lahey1-Jul-13 4:13 jim lahey 1-Jul-13 4:13  If only WTFs could be used as an energy source - the VB6 and PHP legacy code out there could fuel us until entropy. Re: More mining from our deep seam of WTF's Rob Grainger1-Jul-13 4:54 Rob Grainger 1-Jul-13 4:54  Sadly true! "If you don't fail at least 90 percent of the time, you're not aiming high enough." Alan Kay. Re: More mining from our deep seam of WTF's charlieg1-Jul-13 5:10 charlieg 1-Jul-13 5:10  Oh, a sweet quote for sure. Just replace with your topic of choice... Charlie Gilley <italic>You're going to tell me what I want to know, or I'm going to beat you to death in your own house. "Where liberty dwells, there is my country." B. Franklin, 1783 “They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” BF, 1759 Re: More mining from our deep seam of WTF's jim lahey2-Jul-13 22:58 jim lahey 2-Jul-13 22:58  Parameterised and reusable!

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