Why do so many "developers" not understand 'null'?
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I read somewhere, years ago, that zero/nothing is one of the most difficult concepts for the human brain to understand. I think it was suggested that that was why there is no zero in Roman numerals.
It isn't. I have one apple in my hand. How much do you have in yours? Even prehistoric hunters came back with "zero". There's no 0 in Roman Numerals because it would not make sense to count nothing. A farmer that owes no taxes gets ignored, they counted what was owed. "Zero" would have no use there; even if that is the return of your hunting trip, 0 is not recorded. Writing is too precious to record zero's.
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
Addresses of other addresses boggles the mind; until you get the hang of it.
"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
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Give freedom back to 'NULL' to exist. If not: Dear c# designers, please then remove the possibility to define nullable types ;P
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
There is a bridge joining the two buildings in our location. Any "developer" whose code crashes in production because of a bad pointer gets hanged from the bridge pour encourager les autres. So no, this is not a common problem. :) Seriously, all the developers I work with (even the young 'uns) know what a null reference is, and know to avoid it
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows. -- 6079 Smith W.
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Well, in a world where we have programming languages that have concepts like "truthy" and "falsey", what can you expect? :rolleyes:
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There is a bridge joining the two buildings in our location. Any "developer" whose code crashes in production because of a bad pointer gets hanged from the bridge pour encourager les autres. So no, this is not a common problem. :) Seriously, all the developers I work with (even the young 'uns) know what a null reference is, and know to avoid it
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows. -- 6079 Smith W.
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Quote:
Seriously, all the developers I work with (even the young 'uns) know what a null reference is, and know to avoid it
Same here. All the young serious developers I'm working with, know how to handle it.
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It isn't. I have one apple in my hand. How much do you have in yours? Even prehistoric hunters came back with "zero". There's no 0 in Roman Numerals because it would not make sense to count nothing. A farmer that owes no taxes gets ignored, they counted what was owed. "Zero" would have no use there; even if that is the return of your hunting trip, 0 is not recorded. Writing is too precious to record zero's.
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
In Norwegian, the name of numeric zero is 'null'. So Norwegian kids 'sort of' have an excuse for confusing the two. But they are quite different. Zero is a distinct, well defined numeric value that you may treat 100% like any other numeric value. 'null' is nothing, not a numeric value, but a void. Emptiness. An abyss. Not at a valid numeric value. Some programming languages use the term 'void'; it is really much more descriptive. I feel like digging up my old Robert Heinlein collection to re-read the short story—And He Built a Crooked House[^]. The story tells about a crazy architect (in California, obviously :-)) who designs a house which is a 3-dimensional projection of a 4-dimensional cube, a tesseract. The night before the house owners move in, there is an earthquake that makes the house fold up as a true tesseract, in 4 dimensions, not just as a 3-dim projection. I believe that Heinlein has taken liberties in his description of how a real tesseract would appear. But his description of the view out one window, of a total emptiness, not even black, gave me shivers when I first read it, many years ago. It is a beautiful literary description of the concept of a 'null'. I think that I didn't fully understand the concept of null, void, myself until I read the Heinlein story.
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
Richard MacCutchan wrote:
Do those of you who still work in teams find this is a common problem with younger team members?
Yes, all the time. I almost think it is something you have to learn the hard way, because in my experience, most are not aware of this as they code. Now, new IntelliSense with VS 2022 and ReSharper will point this out/alert you right away when it happens, but still, everyone should grok this concept.
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
A guy on the team I just joined was somewhat miffed about the whole nullable feature in C#. He had learned in university that object oriented languages had nullable references. And C# is an object oriented language... so obviously we could not force references to have values.
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
Richard, this is a problem of perception, you seem to think anyone who posts in Q&A is a "developer". Most are probably just learning (and you are their teaching resource) and a lot of them are code monkeys at best.
Never underestimate the power of human stupidity - RAH I'm old. I know stuff - JSOP
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Well, after all it is the Billion Dollar Mistake[^], as Tony Hoare himself put it :-D Recently I had to go through a large code base where the authors went crazy using Non-nullable pointers[^] almost everywhere. What can I say, seems a complicated problem for many people :rolleyes:
Mircea
Mircea Neacsu wrote:
Tony Hoare himself put it
But I'm unsure if he doesn't really believe it himself; nulls are still a very good idea, but dangerous in the wrong hands. But so are chain saws, and hair spray, big deal.
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
trønderen has also said it well. Even the C language has confusion on this topic. Yes, I too believe that they have distinct meanings. Remember my posing the question of why is this a valid statement in C zero = 0; value = malloc( zero ); value is not null nor zero. Why would I want to allocate zero memory? Here is what ChatAI says In the C programming language, calling malloc(0) is allowed and returns a pointer to a memory block of size 0. This is specified in the C standard, which states that malloc(0) is equivalent to malloc(1). The reason for this behavior is that malloc is intended to allocate memory dynamically, and a request for 0 bytes of memory is considered a valid request. Allocating a block of memory with a size of 0 can be useful in certain situations, such as when you want to create a zero-length array or when you want to allocate memory that you will later reallocate to a different size using realloc. However, it is important to note that malloc does not guarantee that it will return a pointer to a block of memory that is truly 0 bytes in size. The implementation of malloc may choose to return a block of memory that is larger than the requested size, in which case the additional memory will not be accessible to your program. Clear as mud.
"A little time, a little trouble, your better day" Badfinger
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
It seems to me not only null is the problem, but programming knowledge in general. Throughout my career I've seen very bad code by very "experienced" people. Not just the young kids, but the old farts too. It's so bad I'm now convinced that about 90% of the people are just plain bad at their job :sigh:
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
Nobody teaches to use a debugger, a real one at least. For my first months in the real World I debugged with printf - I did image analysis. Debugging imaging algorithms by printing 1024x1024 tables of numbers? I did that. One of my dreams is to get a teaching position in CS. I will not let anybody out of the room until they learn to place breakpoints and use the watch window.
GCS/GE d--(d) s-/+ a C+++ U+++ P-- L+@ E-- W+++ N+ o+ K- w+++ O? M-- V? PS+ PE Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
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I have just gone through four QA questions, each of which is an error caused by a null reference. And yet none of the posters seems to have any idea a) how to diagnose and fix it, or b) even what the error means. Do those of you who still work in teams find this is a common problem with younger team members?
Depends on the definition of "young" ;P But, seriously, I see so many powers that be in a high tech company internalize their fears of mistakes by programmers who simply don't get the deeper meaning of a sort-of tri-state logic, so that when when you apply it correctly, you're going to get smacked by individuals who wallow in this fearmongering mindset. Thinking, "if I can't comprehend this to treat the information properly and make a mess, I'm going to force you into that same fear, so that I won't look incompetent and alone". The real issue though, is the hiring policy. Like, who the ***k hired you, and worse, who made you the boss around here? Do you have more skeletons in the closet regarding your pretend-strong, feeble character? Ok I digress. But if you lack the technical grid to understand what your responsibility is towards the state of a variable, you should really be looking for another job. No wonder IT systems have so many vulnerabilities.
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I read somewhere, years ago, that zero/nothing is one of the most difficult concepts for the human brain to understand. I think it was suggested that that was why there is no zero in Roman numerals.
Zero and null are not remotely the same thing. Zero is a value like any other. Null is the absence of any value, "undefined" if you like.
