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'the imperative goto == the object oriented if', both have their uses and allow misuse. The degree of misuse is telling ...
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As with any instruction in any language, improper use will get you into trouble. There are some 470,000 words in Webster's dictionary. Day-to-day we typically use less than 500. The others are there just in case but that doesn't mean we have to use them. The closer to bare metal you get, the more the higher level languages simply carry too much overhead to be practical. In resource-constrained environments you don't have the luxury of being elegant. On a 32K platform you're limited to about 3-5,000 lines of (C) code, you need to be creative and shortcuts save program space. When the need arises for an assembly stub, branches and jumps (assembly level GOTOs) are a way of life.
The GOTO instruction is a tool and like any tool, use it if you need it, but don't use it just because it's there. As it is said, if the only tool in your box is a hammer, you're constrained to build everything with nails, but if you need to nail something, it's useful (not necessary) to have a hammer.
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This question has received lots of humorous responses, now for a slightly more serious one 
Yes, we used to use gotos a lot in the old days (and I'm actually old enough to say that  ).
But my feeling now is that any language where I ever feel the need to use a goto is a flawed language.
But seriously, the original "Go To Considered Harmful" [https://homepages.cwi.nl/~storm/teaching/reader/Dijkstra68.pdf] was a brilliant step in providing discipline to coding to narrow the gap between algorithm design and implementation. A main idea being that gotos break the provability of correctness.
Anybody can tell you that extensive use of gotos was involved in large numbers of defects (thus quite costly).
One other point I'd like to make is that gotos can interfere with optimizers.
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Java replaced goto with labeled break and continue.
They kept goto as a reserved keyword that you cannot use.
I wish C# had followed that model, but I suspect MS decided it was safer to follow C++ (which followed C) for legal reasons. (lawyers designing coding languages!)
C++ made some uses of goto illegal that were allowed in C due to constructor/destructor scope constraints.
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Edsger Dijkstra (March 1968). "Go To Statement Considered Harmful". Communications of the ACM (PDF). 11 (3): 147–148. doi:10.1145/362929.362947. The unbridled use of the go to statement has as an immediate consequence that it becomes terribly hard to find a meaningful set of coordinates in which to describe the process progress. ... The go to statement as it stands is just too primitive, it is too much an invitation to make a mess of one's program.
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The problem with goto is it makes it trivially easy to write spaghetti code. It is also the one of few jump methods available to a computer, so once you get down to the hardware goto (jmp) can be found nearly everywhere.
On the other hand, you can write spaghetti code in any language, even those without goto, simply by not factoring any control structures properly.
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goto overuse makes it very difficult to understand and debug a program. There are legitmate uses of goto, such as breaking out of a loop, but in those cases I would just use the keywords that do the same thing for clarity. I had the joy to try and debug someone's code that was riddled with gotos. He also had the nasty habit of making functions several hundred lines long. I ended up just rewriting everything he wrote. I still feel that was the correct decision, and it only took me a couple days.
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Every programmer is taught that goto leads to spaghetti code. When they are new, they struggle to do without goto, adding termination variables and writing weirdly nested loops.
They pass through an intermediate stage where they occasionally give in to the urge to use goto, typically to get out of a deeply nested loop or in case of error. They then author threads like this one, seeking to justify their need for goto to the world as, "It's not so bad if used <like i="" just="" used="" it="">."
If they don't change careers, and if they keep on improving their skills, developers eventually reach a point where the last time they used a goto is receding in the rearview mirror of time. They write smaller, simpler functions. They don't nest loops so much because they get better at understanding termination conditions. They learn to do tricks with break and continue, which provides somewhat more structured alternatives to the goto.
And they read threads like this one and sigh.
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I rarely use "goto", but when I do it is usually:
- to "break" twice out of some construct. (goto just_past_outer_loop)
- (C) to implement an error handling construct with a clean exit, that jumps to a dedicated piece of rollback code, like
result = criticalaction1();
if (!result) goto error_exit;
result = criticalaction2();
if (!result) goto rollback_action1;
return SUCCESS;
rollback_action1:
undoaction1()
error_exit:
return FAILURE;
"spaghetti code" is a lazy, pseudocritical kind of comment. I hate it with a passion. If a Pavlov response is the only thing you're capable of, you should pick another job. I'm serious.
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My sig line says it all.
If you think 'goto' is evil, try writing an Assembly program without JMP.
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I used basic in the past and for that language GOTO was very convenient for establishing looping and simple procedural content. The reason many teachers discourage it's use is that it can very easily lead to the development of spaghetti code. That said, the presence of a GOTO statement should not be seen as an automatic sign of spaghetti code. GOTO can be used to produce good code that is in no way likely to be judged negatively by a true computer scientist (at least on that basis, alone).
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RandyBuchholz wrote: Have we developed an irrational fear of goto born out of ancient coding dogma? Or is goto inherently and absolutely evil?
Ask anyone any of the following
- Which is better Windows or Linux
- Which is better C#, Python, Java or C++
- Which is better Relational databases or NoSQL databases
- Which is better micro-services or traditional server based solutions.
- Which is better Waterfall or Agile.
- Ask them if they write maintainable and readable code.
And of course then follow up with asking them to specify exactly what objective measurements they took to validate their response. Or even ask them how they would objectively measure it if they had the time and money.
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Are marine creatures all too damselfish to join in?
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
AntiTwitter: @DalekDave is now a follower!
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They are too clammed up.
GCS 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--- ++>+++ y+++* Weapons extension: ma- k++ F+2 X
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You're looking pretty shark today Griff!
... such stuff as dreams are made on
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Indeed. He's off the scales today!
/ravi
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Dressed to krill!
"the debugger doesn't tell me anything because this code compiles just fine" - random QA comment
"Facebook is where you tell lies to your friends. Twitter is where you tell the truth to strangers." - chriselst
"I don't drink any more... then again, I don't drink any less." - Mike Mullikins uncle
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I hear he prawned most of his worldly possessions in order to buy those duds.
/ravi
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I imagine he has to sponge off people to survive.
"the debugger doesn't tell me anything because this code compiles just fine" - random QA comment
"Facebook is where you tell lies to your friends. Twitter is where you tell the truth to strangers." - chriselst
"I don't drink any more... then again, I don't drink any less." - Mike Mullikins uncle
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Not all marine creatures are shellfish. Many do expect a squid pro quo arrangement, though, and are inclined to get a bit crabby if you simply mussel in on their action.
98.4% of statistics are made up on the spot.
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Cetacean required.
“That which can be asserted without evidence, can be dismissed without evidence.”
― Christopher Hitchens
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I thought about it a whale and, as is off-fin the case, it spawned some ideas which eel discuss another time.
| Ravings en masse^ |
|---|
| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you are seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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I started a new job on Monday and found that everything (Windows) is Windows 10 (Enterprise). Good old Windows 7 is gone, gone, gone, dammit!
However, having been a protestant against this exercise in form over function (possibly worse than iCrap) for a long time, I am now forced to use it to earn a living - and they are paying me a lot more than my previous job so my policy is now not to complain but to accept and adapt.
In addition, since this is a government (county) job they are doing wonderful things like not letting developers be administrators of their own machines restricting what we can change and/or install. I am now finally on VS2017 which seems to actually be working OK at the moment. Oh, and can anyone spell GIT? We are moving from the perfectly acceptable TFS to GIT for some reason so a lot of the existing projects (over 500 of them) are being transitioned or are half and half, which is very confusing.
They also appear to hate gmail and block all access to it. Luckily, Code Project is OK.
I'll let you know how it goes as I get more used to this flat, visually... (what's the opposite of "stunning"?), yet confusing interface.
[update] Although using GIT I cannot install a Visual Studio GIT extension as this requires admin permissions - which I don't have!
- I would love to change the world, but they won’t give me the source code.
modified 8-Jun-18 9:22am.
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Forogar wrote: (what's the opposite of "stunning"?),
Numbing? That's definetely what I feel using Win10.
GCS 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--- ++>+++ y+++* Weapons extension: ma- k++ F+2 X
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"Numbing" - perfect!
The main problem I have is there is no indication of which window is "on top" of which other window since there are no 3-D borders or shadows that give your eye the cues it needs.
A few times a window has popped up but is wasn't obvious because the thin lines at the edges lined up with existing thin lines on the window underneath so I didn't notice any change especially when I am working on three wide screens and sometimes the window comes up "over there" instead of here where I am looking and expecting it!
- I would love to change the world, but they won’t give me the source code.
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