Re:Modern C [pdf]
by btilly on Wednesday November 30, 2016 @12:33PM
(#13072711)
It is not that RAII is non-obvious after you've worked with it. It is that you can read through how the language works somewhere like http://www.cplusplus.com/doc/tutorial/, start producing software, and not realize that you have to do RAII. You can even, as Google did, have experienced and competent people write a large and well-structured program and then only belatedly realize that you can't use certain features because they didn't structure the program right.
There is a lot of that in C++. If you get everything right, then wonderful. If you don't, then that is a problem.
On implementation bugs, I have found implementation bugs in lots of languages. But not generally as things that I stumble over while proceeding with what seems to me like it should be the obvious thing to try.
With C++ it isn't like that. I gave you an example where there is a disagreement between compilers. But, for example, what happens if I supply an ordering method that isn't consistent? In other languages I get stuff sorted slightly inconsistently. In C++ I get a core dump. Good luck figuring out why.
On the complaint that you have about Java, that falls in the category of things that I expect to have to deal with. Part of my mental model for a language has to be the memory management rules. C++ lets you set up whatever you want. Perl does deterministic destructors but therefore can't collect circular data structures without help. Java has true garbage collection so it collects circular data structures, but it can't guarantee that they are collected in a timely way. JavaScript does true garbage collection now, but back in the IE 4.0/5.0 days they separately collected garbage for native objects and JavaScript objects with the result that garbage never got collected if there was a cycle between native and JavaScript objects.
This is one of the basic facts that I know that I have to understand about any language I work with. It is like pass by value vs pass by reference, or the scoping rules. I immediately look for it, understand it, and then am not surprised at the consequences. I see other people use the language for a while without trying to understand that. I understand their pain. But I'm not caught by surprise.
However C++ keeps finding new ways to surprise me. In the past I reserved it for cases where I need to implement an algorithm and squeeze and order or two new magnitudes of precise memory layout and performance beyond what is available in scripting languages. I've resolved that the next time I need that, I'll try a new language. My past experiences with C++ haven't been worth it.
There is a lot of that in C++. If you get everything right, then wonderful. If you don't, then that is a problem.
On implementation bugs, I have found implementation bugs in lots of languages. But not generally as things that I stumble over while proceeding with what seems to me like it should be the obvious thing to try.
With C++ it isn't like that. I gave you an example where there is a disagreement between compilers. But, for example, what happens if I supply an ordering method that isn't consistent? In other languages I get stuff sorted slightly inconsistently. In C++ I get a core dump. Good luck figuring out why.
On the complaint that you have about Java, that falls in the category of things that I expect to have to deal with. Part of my mental model for a language has to be the memory management rules. C++ lets you set up whatever you want. Perl does deterministic destructors but therefore can't collect circular data structures without help. Java has true garbage collection so it collects circular data structures, but it can't guarantee that they are collected in a timely way. JavaScript does true garbage collection now, but back in the IE 4.0/5.0 days they separately collected garbage for native objects and JavaScript objects with the result that garbage never got collected if there was a cycle between native and JavaScript objects.
This is one of the basic facts that I know that I have to understand about any language I work with. It is like pass by value vs pass by reference, or the scoping rules. I immediately look for it, understand it, and then am not surprised at the consequences. I see other people use the language for a while without trying to understand that. I understand their pain. But I'm not caught by surprise.
However C++ keeps finding new ways to surprise me. In the past I reserved it for cases where I need to implement an algorithm and squeeze and order or two new magnitudes of precise memory layout and performance beyond what is available in scripting languages. I've resolved that the next time I need that, I'll try a new language. My past experiences with C++ haven't been worth it.