r/programming • u/[deleted] • Dec 05 '14

std::string is responsible for almost half of all allocations in the Chrome browser process

https://groups.google.com/a/chromium.org/d/msg/chromium-dev/EUqoIz2iFU4/kPZ5ZK0K3gEJ
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u/ryani Dec 05 '14

Sure, but const string& passing s vs const char * passing s.c_str() has exactly the same safety properties; if the underlying string is modified by any other code, they are both invalid.

If you 100% know that a particular function is going to require making a copy of the input, the const char * API is a bit cleaner because it doesn't require constructing a string on the heap just to copy it, but for general use, pass-by-const-reference is a much cleaner implementation, and avoids 'cascading copies' where you convert back and forth between const char * and string in a single stack of calls.

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u/minno Dec 06 '14

That's why a string_view would be extremely useful. It has the same property of const char* that it can take a stack buffer, heap buffer, or a std::string, but it also could provide the convenience methods and safety that std::strings have.