Taking the following example:
void foo(const int foobar);
Is the keyword const meaningful?
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Yes, obviously. Your function foo() will not be able to modify the value foobar inside the function.
Sourav Ghosh
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Hi Sourav; hope you're fine. "will not be able"... This is wrong. In C, `const` is a promise by the programmer not to change, not enforced by the compiler/runtime. – too honest for this site Aug 04 '15 at 13:57
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@Olaf sorry, but attempting so will generate comp-err, right? – Sourav Ghosh Aug 04 '15 at 13:58
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You can cast away the const, still using the same object (yes, that should generate a warning, but, hey warning is better than error ...;-) – too honest for this site Aug 04 '15 at 13:59
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Same here. Still busy. – too honest for this site Aug 04 '15 at 14:00
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@Olaf ahh, that way, it's _bypassed_. At least, for the first time, without the cast, we'll get to know, we should not have changed that....... :-) – Sourav Ghosh Aug 04 '15 at 14:01
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2Yeah, I'm a destructive bastard;-) - one reason I have to be careful writing code, if I'm not, it breaks when I test already. Other people manage to surf around their bugs (unintended). FYI: In other languages, like Python, you can make objects true read-only using e.g. properties. Any access will result in runtime exception. In C, there is no guarantee about this, just UB. – too honest for this site Aug 04 '15 at 14:05
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@Olaf Can't agree more to the later part of the comment sir . :-) – Sourav Ghosh Aug 04 '15 at 14:06
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2Pew, I was already wondering what part the +1 was for ;-) – too honest for this site Aug 04 '15 at 14:07
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@Olaf That's why I explained. ;-) – Sourav Ghosh Aug 04 '15 at 14:08
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I guess the larger question is 'who would care?'. The parameter is a value copy anyway. – Martin James Aug 04 '15 at 14:54
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@MartinJames maybe the developer would, who doesn't want the maintainer to _alter_ the input parameter, for _some_ reason. :-) – Sourav Ghosh Aug 04 '15 at 15:01
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@SouravGhosh sure, yes. It's just that I'm struggling to think of an example here I may want to do that:) – Martin James Aug 04 '15 at 15:19