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Coming from assembly language, I always found the anti-goto sentiment rather cute. A beautiful restriction, but ultimately arbitrary. Like writing poetry. Or those novels that do not ever use the letter "e". Why would an otherwise sane person write code with "rep" and without ever using "jmp"?
The compiler converts a function with a yield command into a label. To resume a function from where it left off, the compiler adds code to test an added resumption-point variable and to goto the label for each resumption point.
There are a few situations like this, where a bad practice is in a specific case good enough: Using goto to bail out multiple levels, using SHA-1 as a non-secure hash, ... The problem is these things waste social bandwith: Someone reading your code for maintenance or code review will first declare the code bad (GOTO is ugly! SHA-1 is insecure!), then you have to signal to them that it's actually OK in this case, then…
Then Apple comes with the glorious "goto fail" and shows that real companies use goto, and the problem wasn't "goto" itself.
Earlier quoted context omitted.
It's not arbitrary. The goal is to improve quality by making the code better structured and easier to follow. For instance, MISRA C rule 15.1 that states that goto should not be used explains: " Unconstrained use of goto can lead to programs that are unstructured and extremely difficult to understand ". Indeed, in practice that's often the case.
Well, in C you very rarely need it, but in assembler (particularly the 8-bit Z80 and 6502 that I've written raft-loads of code for) you definitely do. Of course, something like a CALL is better, if you can manage it.
Coming from assembly language, I always found the anti-goto sentiment rather cute. A beautiful restriction, but ultimately arbitrary. Like writing poetry. Or those novels that do not ever use the letter "e". Why would an otherwise sane person write code with "rep" and without ever using "jmp"?
Earlier quoted context omitted.
Well, in C you very rarely need it, but in assembler (particularly the 8-bit Z80 and 6502 that I've written raft-loads of code for) you definitely do. Of course, something like a CALL is better, if you can manage it.
goto is the idiomatic way to emulate RAII in C. It's everywhere.
The only acceptable use-case for goto I came across was for error handling and cleanup. If there are multiple points of code failure that all require same cleanup procedure then one section at the bottom is acceptable and can actually keep the code cleaner. Anything else looks like bad design that ends up producing hard to follow code.
rc = do_something();
if (!rc) {
rc = do_something_else();
}
...
do_cleanup();
rc = do_something();
if (rc) goto xout;
rc = do_something_else();
...
xout:
do_cleanup();
Coming from assembly language, I always found the anti-goto sentiment rather cute. A beautiful restriction, but ultimately arbitrary. Like writing poetry. Or those novels that do not ever use the letter "e". Why would an otherwise sane person write code with "rep" and without ever using "jmp"?
There is no need to use GOTO when a language has functions/procedures and exceptions.
Of course it makes sense in Assembly or more rudimentary languages, or in specific cases for speed optimization (getting out of multiple loops).
However, I must admit, sometimes I'm sick of the way Go "deals" with errors so I resort to GOTO to manage HTTP errors in my HTTP request handlers.