4 ms·

Yes, and he's said that in a few blog posts as well: http://herbsutter.com/2013/06/07/gotw-92-solution-auto-variables-part-1/ http://herbsutter.com/2013/06/07/

by jobu 12y ago

Yes, and he's said that in a few blog posts as well: http://herbsutter.com/2013/06/07/gotw-92-solution-auto-variables-part-1/ http://herbsutter.com/2013/06/07/gotw-92-solution-auto-varia... http://herbsutter.com/2013/06/07/gotw-93-auto-variables-part-2/ http://herbsutter.com/2013/06/07/gotw-93-auto-variables-part... http://herbsutter.com/2013/08/12/gotw-94-solution-aaa-style-almost-always-auto/ http://herbsutter.com/2013/08/12/gotw-94-solution-aaa-style-... He has some good points, but his perspective seems to be biased by a professional focus on writing libraries and more general-purpose code. He's also brilliant and can remember things like this: const int& cir = val; auto h = cir; //The type of h is int. It's difficult to make generic rules for how to use C++ (because it's used for everything from adware to nuclear reactors), but I can say that Herb's AAA (Almost Always Auto) rule would not fly on any development team I've ever worked with.

swift 12y ago
The type of h isn't so hard to understand, there. |auto| gives you a value; if you want a reference, use |auto&|. This rule actually makes |auto| more readable: you always know if you're looking at a reference or not. Probably you expected |auto| to behave like |decltype()|, C++11's other form of type deduction, which gives you the actual type of an expression. C++14 adds |decltype(auto)|, which lets you declare local variables using this behavior if you want it. I'm not sure whether I'd apply Herb's AAA rule quite as broadly as he suggests, but I think it's broadly right, because far too often in C++ we write a type twice on the same line, which is just redundant. I vastly prefer |auto val = new MyClass;| to |MyClass val = new MyClass;|, and similarly |auto casted = static_cast<MyType>(uncasted);| is completely readable without typing writing "MyType" a second time. C++ programmers are a conservative lot, but I expect using |auto| at least in those cases to be pretty mainstream within a few years.

by jobu 12y ago

swift 12y ago

The type of h isn't so hard to understand, there. |auto| gives you a value; if you want a reference, use |auto&|. This rule actually makes |auto| more readable: you always know if you're looking at a reference or not. Probably you expected |auto| to behave like |decltype()|, C++11's other form of type deduction, which gives you the actual type of an expression. C++14 adds |decltype(auto)|, which lets you declare local variables using this behavior if you want it. I'm not sure whether I'd apply Herb's AAA rule quite as broadly as he suggests, but I think it's broadly right, because far too often in C++ we write a type twice on the same line, which is just redundant. I vastly prefer |auto val = new MyClass;| to |MyClass val = new MyClass;|, and similarly |auto casted = static_cast<MyType>(uncasted);| is completely readable without typing writing "MyType" a second time. C++ programmers are a conservative lot, but I expect using |auto| at least in those cases to be pretty mainstream within a few years.