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GuyThiebaut wrote: use a return statement in code which in essence is a goto.
No, it's that other thing, calling and returning from subroutines. A totally different animal, down to the machine code of the processor.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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GuyThiebaut wrote: Back in 1988
GuyThiebaut wrote: the first year had 2 hours of computer time each week. Most of our work was done on paper.
I remember those days well!...being a CS major from around '87 to '89 when my part-time afternoon job turned into full-time, which meant almost no lab time. I quit school for 10 years and finally went back and finished. During my 10 year hiatus, I had very little contact with computers so coming back to it after a decade I was more than a little pleased to find that I could finally do homework at home...even in the wee hours of the morning! 
Somewhere in a box, in a closet, are notebooks with handwritten C, Pascal, and Fortran homework assignments. I also have some greenbar printouts with notes/grade. Deliverables for an assignment were typically handwritten pseudo-code and/or flowchart and the printout which contained source code and results. That junk probably won't make the next move! 
It amazes me now to think about how different it was to learn programming back then. Nowadays, an answer to a question is usually just a few clicks away, back then we relied on books, our own wits, and occasionally teachers/aides who sometimes knew little more than we did. 
Thanks for the memories!
"Go forth into the source" - Neal Morse
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Thanks for the post!
I am ambivalent as to whether I would rather learn CS now or back in the 80's.
Back in the 80's there was no WWW or everything that came with it(given the internet did exist with JANET being the network we had access to).
In some ways I think people have it harder nowadays because there is so much more to learn.
On the other hand a kid with a laptop and network connection can easily educate themselves, to the same level I was at when I graduated, before they even start their course in CS.
I think we expect more of graduates nowadays than we did back in the 90's when it was a given that your first few years would be on the job training and you understood that when you graduated that you basically knew very little.
“That which can be asserted without evidence, can be dismissed without evidence.”
― Christopher Hitchens
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For several years programmers have had OOAD and OOP pounded into their heads, and goto is an inherently structured code construct. If you use goto in an object oriented program, you are creating spaghetti code, which is why that particular reflex exists.
"There are three kinds of lies: lies, damned lies and statistics."
- Benjamin Disraeli
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I don't have an existentialism issue with goto.
It can have its uses, very limited, but can be useful.
We have a few in some of our older legacy C code.
None in the new C++ code.
I'd rather be phishing!
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It's not an irrational fear: it's a sensible precaution.
goto is a "shortcut" for lazy lecturers and lazy students - it positively encourages poor quality code and bad habits. That doesn't mean it shouldn't be used, just that you have to understand why you aren't using it before you should be allowed to use it. It has its place (try doing assembly code, or time critical embedded C / C++ without it) but generally speaking it's a bad idea in "modern" languages which have rich flow control constructs and a set of good practices which should mean that it isn't that necessary. For example, I've been coding in C# for nine years now, and not once have I needed to use a goto, nor have I had to "fudge round" not using one.
It annoys me when it's taught early because the idiot running the course can't be bothered to teach a while, for, or foreach loop to beginners. Because once you start using a hammer, every problem looks like a nail...
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
AntiTwitter: @DalekDave is now a follower!
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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? 
Are we asking annoying questions, just for the sake of asking?
Jumping to a label was once an improvement ovr jumping to a specific linenumber. You are doing as if using a "GOTO 40" still has a place in modern C# coding. It doesn't.
No, it's not a dogma; you don't have to believe me and can feel free to GOTO anywhere in your code - it will be your problem, not mine
Bastard Programmer from Hell 
If you can't read my code, try converting it here[^]
"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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Quote: Are we asking annoying questions, just for the sake of asking?
No, not just for the sake of asking, just for the sake of annoying.
Also to see how many mind readers would jump on me for using them - even though I didn't say I used them. And don't, except in rare, low-level performance cases.
It came out of a recent discussion. I was reviewing some code someone showed me (they didn't write it) that had a goto in it. He said the code was Spaghetti Code. When I asked why, he said because it had a goto. I asked why that made it spaghetti, and all he could come up with was that he was taught that. I asked about a few other "programming truths", and had much the same response. This is good, that is bad, but I don't really know why. I started thinking about how for some things, aspects of programming have become more faith than science.
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RandyBuchholz wrote: even though I didn't say I used them.
That's not relevant to me, you're implying they may not be bad.
RandyBuchholz wrote: This is good, that is bad, but I don't really know why. I started thinking about how for some things, aspects of programming have become more faith than science.
No, it hasn't. We have simple rules for the monkeys to follow; anyone who can actually think doesn't need them. So we can't do without that faith, since some people continously ignore everything in the manual.
While I agree that a single goto won't kill anyone, I also haven't seen any practical C# example where using one would be justified.
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
"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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Add this info on your original post.
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This old chestnut again  there are better constructs available with less risk of abuse. I've not used a goto in well over 20 years and am quite happy to leave it that way.
Never underestimate the power of human stupidity
RAH
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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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