3 ms·

Yes, that's correct. It is, in fact, the same kind of behavior you get with templated code: you can instantiate your template with any type you wish; compile er

by thebear 12y ago

Yes, that's correct. It is, in fact, the same kind of behavior you get with templated code: you can instantiate your template with any type you wish; compile errors will occur when the instantiation is used in ways that are forbidden by the type. This behavior has been recognized as less than ideal, and the issue will be addressed by concepts. My question is: if we have this behavior not only for templates, but for every variable, isn't that less type-safety? Isn't that less than 'strongly typed'? (Come to think of it, I think I'm really asking about the definition of 'strongly typed'.)

scott_s 12y ago
Indeed you are. There was a post from two weeks ago on the topic, called "What is type safety?" HN discussion here: https://news.ycombinator.com/item?id=8137332 https://news.ycombinator.com/item?id=8137332
squeaky-clean 12y ago
>My question is: if we have this behavior not only for templates, but for every variable, isn't that less type-safety? It depends on how you code, I suppose. I use var very frequently in C# now after being averse to it at first. I've never run into an issue where var caused problems in my code (rarely my IDE won't be able to pick up on what type it should be, but it compiles fine). If you're changing a variable between compatible types, like a parent class, or changing to a different type of enumerable class where usage is exactly the same, you don't really run into issues. If you're changing the entire usage of a class (like from a vector to an array, or something even more different) than you probably should not simply re-declare the variable, you should be rewriting that code. You wouldn't change vector<int> numbers = new vector<int>; to int* numbers = new int[512]; Without making accommodating changes to the following code, would you? Then you shouldn't change auto numbers = new vector<int>; to auto numbers = new int[512]; Without making changes to the rest of the code either. It's exactly the same as before, except you get to type less and it clutters the screen less when you don't need to write types multiple times on the same line. Especially for very long types names.

by thebear 12y ago

scott_s 12y ago

Indeed you are. There was a post from two weeks ago on the topic, called "What is type safety?" HN discussion here: https://news.ycombinator.com/item?id=8137332 https://news.ycombinator.com/item?id=8137332

squeaky-clean 12y ago

>My question is: if we have this behavior not only for templates, but for every variable, isn't that less type-safety? It depends on how you code, I suppose. I use var very frequently in C# now after being averse to it at first. I've never run into an issue where var caused problems in my code (rarely my IDE won't be able to pick up on what type it should be, but it compiles fine). If you're changing a variable between compatible types, like a parent class, or changing to a different type of enumerable class where usage is exactly the same, you don't really run into issues. If you're changing the entire usage of a class (like from a vector to an array, or something even more different) than you probably should not simply re-declare the variable, you should be rewriting that code. You wouldn't change vector<int> numbers = new vector<int>; to int* numbers = new int[512]; Without making accommodating changes to the following code, would you? Then you shouldn't change auto numbers = new vector<int>; to auto numbers = new int[512]; Without making changes to the rest of the code either. It's exactly the same as before, except you get to type less and it clutters the screen less when you don't need to write types multiple times on the same line. Especially for very long types names.