Interrupt startup / abort programm start in main()
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@jsulm I like
goto, not likeif..else.void Fun() { if(true){goto _OK;} if(false){goto _END;} if(true){goto _OK;} if(false){goto _END;} if(true){goto _OK;} if(false){goto _END;} if(true){goto _OK;} /**...*/ _OK: return true; _END: return false; } void Fun() { if(true) { if(true) { return false; } else { if(true) { return true; } return false; } return true; } else if(true) { return true; } else { return false; } }so, I like use
goto.@joeQ goto is very bad style.
Your example is bad: if (true) will always evaluate to true...
But it is up to you how you program. -
@joeQ goto is very bad style.
Your example is bad: if (true) will always evaluate to true...
But it is up to you how you program.@jsulm Yes, Many people think
gotois bad style.But, I like it. and,
if(true)meansif(condition), not always return true. usegoto, is my personal programming habits. I think the programming habits can help me.many times, use
gotois up to program. You are right..This is my Chinese blog about How to use goto. You can see the code example.
if elseis good. andgotois not bad. Just you can enhanced readability of the program. They are the best.Just do it!
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@jsulm Yes, Many people think
gotois bad style.But, I like it. and,
if(true)meansif(condition), not always return true. usegoto, is my personal programming habits. I think the programming habits can help me.many times, use
gotois up to program. You are right..This is my Chinese blog about How to use goto. You can see the code example.
if elseis good. andgotois not bad. Just you can enhanced readability of the program. They are the best.@joeQ I agree there are rare cases a goto can make sense, but in most cases it just creates a confusing mess. Do you know switch(...) statement in C++? In my whole career I cannot remember to have used goto by myself and I cannot remember to have seen my colleagues using it (we do code reviews, so I know what they write). Do you develop software in a team?
I cannot check your example as your blog does not load here.
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@jsulm Yes, Many people think
gotois bad style.But, I like it. and,
if(true)meansif(condition), not always return true. usegoto, is my personal programming habits. I think the programming habits can help me.many times, use
gotois up to program. You are right..This is my Chinese blog about How to use goto. You can see the code example.
if elseis good. andgotois not bad. Just you can enhanced readability of the program. They are the best.@joeQ Now it finely loaded. To your example: for this you should use smart pointers in C++, this way you make sure the memory is released (you even do not have to do it manually!). See: http://www.cplusplus.com/reference/memory/unique_ptr/
Using smart pointers in your example there would not be any need to delete the memory - it will be done for you as soon as the smart pointers go out of scope.
In general, in modern C++ you should avoid to use raw pointers, use smart pointers instead. -
Avoid
gotoand::exit()as the plague! The first one is a C remnant that dates back to asm'sjmpinstruction and has no place in good code, ever! The second one will allow destructors to be called only on some variables (i.e. global ones), everything else is left in a inconsistent state, so the less you useexitthe better.The "good" solution here, and in most cases, is to just give up as early as possible by returning the appropriate error code, e.g.:
int main(int argc, char ** argv) { QApplication app(argc, argv); if (something_bad) return 1; // Calling ::exit will not allow QApplication to clean up // ... more code return QApplication::exec(); }Read and abide by the Qt Code of Conduct
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@joeQ Now it finely loaded. To your example: for this you should use smart pointers in C++, this way you make sure the memory is released (you even do not have to do it manually!). See: http://www.cplusplus.com/reference/memory/unique_ptr/
Using smart pointers in your example there would not be any need to delete the memory - it will be done for you as soon as the smart pointers go out of scope.
In general, in modern C++ you should avoid to use raw pointers, use smart pointers instead.@jsulm oh, Thanks and regards. I will try smart pointers in C++. And, I never used
gotoin university. and my teacher tell us,gotois bad style like you. but, when i join the software team. my leader is better than us. he is C programer. and, he let every body to usegotoin program. now i am working.
Thank you every much. -
Avoid
gotoand::exit()as the plague! The first one is a C remnant that dates back to asm'sjmpinstruction and has no place in good code, ever! The second one will allow destructors to be called only on some variables (i.e. global ones), everything else is left in a inconsistent state, so the less you useexitthe better.The "good" solution here, and in most cases, is to just give up as early as possible by returning the appropriate error code, e.g.:
int main(int argc, char ** argv) { QApplication app(argc, argv); if (something_bad) return 1; // Calling ::exit will not allow QApplication to clean up // ... more code return QApplication::exec(); } -
@kshegunov @jsulm You said
gotois bad style. But, thegoogle's go languagehas thegotocommand. why didn't removegoto? Every body saidgotois bad. why didn't remove it. It is bad, but it si at here.@joeQ Because in very rare cases it can be useful. Another reason: code generators - it is much easier to write a code generator which uses goto, and generated code is usually not read that often, so goto disadvantages are not a big issue.
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@joeQ Because in very rare cases it can be useful. Another reason: code generators - it is much easier to write a code generator which uses goto, and generated code is usually not read that often, so goto disadvantages are not a big issue.
