(I work at Google and use C++ there, but what follows is my opinion)
What precisely don't you like about the C++ style guide? (This is almost identical to the internal guide)
- It is true that exceptions are verboten, but honestly it's not particularly limiting. Java gets exceptions right - something is truly "impossible" (in a crash-the-program you-have-a-logic-error sense) and thus you don't need to handle it, or else it's "expected" like an I/O issue and the language forces you to do something with it - either try/catch, or declaring that you're potentially passing it along. C++ doesn't have any such enforcement, which makes it very hard to reason about what a function may throw at you. You rely on everybody in the entire call hierarchy doing the right thing. Reminiscing about my Java days, the lack of exceptions does make some things somewhat more cumbersome to deal with - having to explicitly return a status object, for instance, to deal with plausible-but-atypical cases. But the Google guide is fairly apologetic in this area and basically says "sure, we'd use it if we had a brand-new codebase, but we don't..." and the reasons that follow for why exceptions are hard to integrate into a truly enormous codebase seem sound to me. What do you disagree with about this reasoning?
- There is certainly no rule about "allocate at the top, clean up at the bottom, never return from the middle". In fact, with unique_ptr and the like, there's even less reason to do those kind of things than there's ever been. The local variable part of the style guide actually explicitly encourages as-close-as-possible declaration, and the rest of the style guide is quite gung-ho about unique_ptr (we actually had an internal class for a long time that was sufficiently identical to unique_ptr that they were able to replace all uses and remove the custom type in just a few months). I can find no reference to any sort of prescription about the location of return statements.
- The standard libraries have actually been moving away from exceptions, haven't they? C++11 introduced 'noexcept' and added it to a bunch of methods, and the specs for a lot of other ones guarantee that the only exceptions are from the allocator (e.g. std::bad_alloc). To be clear there is no prohibition against *using* code (especially the standard library) that may throw exceptions.
In a nutshell the style guide is, in order, "be readable" followed by "be consistent". It is hilariously easy to write unreadable, bug-prone C++ code. Nobody cares if your code is perfect and correct, they care if the next guy along can modify or use it correctly and it is useful to have a style guide to make some of the more hard to reason about things impossible. How many different bits of code could the statement 'a = b;' potentially execute? (It's a lot - copy constructor, operator=, operator Foo(), etc.) The style guide limits it to just a few things you might have to consider, so that when you use some code someone wrote 6 years ago there's not so much to look at. C++ has references and pointers, which is great, but at least with pointers there's a hint that you might have "spooky action at a distance" so the guide mandates their use for out-params which seems perfectly reasonable since it's basically arbitrary which to use - and in practice, it's a really handy hint to have when you're reading. Unless you're passing an address, you know your copy can't be modified. IMO, way more readable.
If you've really been hanging up on recruiters because you object to the style guide, it is probably worthwhile to actually ensure that your understanding of it is correct and up to date. It has changed in recent years as C++11 has become better understood and it is fair to say that it is far more liberal to things like lambdas, template metaprogramming, operator overloading, copyable classes, etc - than it was a few years ago.
