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For a relatively recent problem caused by use of goto: https://en.m.wikipedia.org/?title=Goto_fail https://en.m.wikipedia.org/?title=Goto_fail

Sniffnoy 8y ago
Non-mobile link: https://en.wikipedia.org/wiki/Unreachable_code#goto_fail_bug https://en.wikipedia.org/wiki/Unreachable_code#goto_fail_bug
zzo38computer 8y ago
That is not specific to do with a goto command itself; even if you wrote "break" instead of "goto fail", still the second one is unconditional. But either way, can easily seen that such program is not sense, so, easily to be noticed. "There are several good coding practices that could have prevented this fault from occurring, such as code reviews, the proper use of indentation or curly braces, and test coverage analysis." Yes, it is true, whether you use goto or not, whether indentation-sensitive syntax is used or not, etc.
- RustHacker 8y ago
  Break is technically a goto, albeit a nicer, more well behaved version thereof.
  - goto11 8y ago
    'if' is also technically a goto then.
    - 13of40 8y ago
      Earlier this year I spent some time implementing a BASIC (actually VBA) interpreter and to support error handling (e.g. ON ERROR GOTO foobar) I ended up translating all of the flow control statements into conditional GOTOs.
goto11 8y ago
The problem is not caused by the use of goto though. It could have been any other statement and it would still be a bug. The problem is lack of braces or the misleading indent. If anything this example is a case for Python, not a case against goto.
- coldtea 8y ago
  >If anything this example is a case for Python, not a case against goto. You'd be surprised how many times I've got the indentation wrong in Python. If a body gets > 20 lines or so, it's easy to miss one statement that ought to be intended.
  - yesenadam 8y ago
    that ought to be intended. That ought to be "indented".
    - coldtea 8y ago
      Yeah, that mistake was inindented
      - yesenadam 8y ago
        Sometimes (like now) I wish I could give a +10 or +100 on HN! Thank you :-)
- int_19h 8y ago
  This example is a case for languages where the bodies of conditionals, loops etc are required to have a terminator. Python is technically one of them, but probably not the best one, because terminator is the DEDENT pseudo-token, and because it's just whitespace, it can be easy to miss. The best examples are languages like Lua and Ruby, where you have to write it as if .. then .. end or if .. then .. else .. end. Alternatively, in the curly brace family, it's the ones that make braces mandatory in this situation, like Go - if ... { ... }.
deleted 8y ago
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Sniffnoy 8y ago

Non-mobile link: https://en.wikipedia.org/wiki/Unreachable_code#goto_fail_bug https://en.wikipedia.org/wiki/Unreachable_code#goto_fail_bug

zzo38computer 8y ago

That is not specific to do with a goto command itself; even if you wrote "break" instead of "goto fail", still the second one is unconditional. But either way, can easily seen that such program is not sense, so, easily to be noticed. "There are several good coding practices that could have prevented this fault from occurring, such as code reviews, the proper use of indentation or curly braces, and test coverage analysis." Yes, it is true, whether you use goto or not, whether indentation-sensitive syntax is used or not, etc.

RustHacker 8y ago
Break is technically a goto, albeit a nicer, more well behaved version thereof.
- goto11 8y ago
  'if' is also technically a goto then.
  - 13of40 8y ago
    Earlier this year I spent some time implementing a BASIC (actually VBA) interpreter and to support error handling (e.g. ON ERROR GOTO foobar) I ended up translating all of the flow control statements into conditional GOTOs.

goto11 8y ago

The problem is not caused by the use of goto though. It could have been any other statement and it would still be a bug. The problem is lack of braces or the misleading indent. If anything this example is a case for Python, not a case against goto.

coldtea 8y ago
>If anything this example is a case for Python, not a case against goto. You'd be surprised how many times I've got the indentation wrong in Python. If a body gets > 20 lines or so, it's easy to miss one statement that ought to be intended.
- yesenadam 8y ago
  that ought to be intended. That ought to be "indented".
  - coldtea 8y ago
    Yeah, that mistake was inindented
    - yesenadam 8y ago
      Sometimes (like now) I wish I could give a +10 or +100 on HN! Thank you :-)
int_19h 8y ago
This example is a case for languages where the bodies of conditionals, loops etc are required to have a terminator. Python is technically one of them, but probably not the best one, because terminator is the DEDENT pseudo-token, and because it's just whitespace, it can be easy to miss. The best examples are languages like Lua and Ruby, where you have to write it as if .. then .. end or if .. then .. else .. end. Alternatively, in the curly brace family, it's the ones that make braces mandatory in this situation, like Go - if ... { ... }.

deleted 8y ago

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