Const declaration curiosity

Question

Ok, so i'm doing some exercise from a book, and I saw this declaration

float f, const c =9.9;

Initially, I thought this would be a compiler error, but I went into VS2013 and tested this, and it did not throw an error. I could even modify the c variable after declaration. I would like to know why and how is this possible,what is the compiler even doing with the const keyword in this case?

`int main() { float f, const c =9.9; }` does not compile with GCC 4.9.2 with `-std=c++11` — tsuki, Jun 09 '15 at 11:02
What book are you reading? When is it from? This seems like something from C in the pre-standard times. — Some programmer dude, Jun 09 '15 at 11:03
The Visual C's `cl` command from Visual Studio 2010 says `warning C4228: nonstandard extension used : qualifiers after comma in declarator list are ignored` which explains why you can modify c and why it doesn't work on gcc/clang — deStrangis, Jun 09 '15 at 11:07
I'm sorry @VictorPolevoy, I forgot to say, this book has only exercises, no theory. — Ryncops, Jun 09 '15 at 11:26
@Rndp13 It's called C++ Secrets, by Constantin Galatan, a romanian exercise book. — Ryncops, Jun 09 '15 at 11:27
You better burn the book and instead pick one from [The Definitive C++ Book Guide and List](http://stackoverflow.com/questions/388242/the-definitive-c-book-guide-and-list) — RedX, Jun 09 '15 at 11:46
@RedX well, I would gladly, but I have an exam in OOP and these exercises are similar to the ones I get in the exam. — Ryncops, Jun 09 '15 at 12:24

score 1 · Accepted Answer · answered Jun 09 '15 at 11:43

1

I would like to know why and how is this possible,what is the compiler even doing with the const keyword in this case?

It's not compiling it. Not with C++14, nor C++11, nor C++03, not even C.

answered Jun 09 '15 at 11:43

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Const declaration curiosity

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