CODEWITHSUNDEEP
c++unicodestlstringstream
Pedro d'Aquino
Pedro d'Aquino

Reputation: 5220

How does std::stringstream handle wchar_t* in operator<<?

Given that the following snippet doesn't compile:

std::stringstream ss;
ss << std::wstring(L"abc");

I didn't think this one would, either:

std::stringstream ss;
ss << L"abc";

But it does (on VC++ at least). I'm guessing this is due to the following ostream::operator<< overload:

ostream& operator<< (const void* val );

Does this have the potential to silently break my code, if I inadvertently mix character types?

Upvotes: 9

Views: 16808

Answers (2)

Steve Townsend
Steve Townsend

Reputation: 54148

Yes - you need wstringstream for wchar_t output.

You can mitigate this by not using string literals. If you try to pass const wstring& to stringstream it won't compile, as you noted.

Upvotes: 14

CB Bailey
CB Bailey

Reputation: 791869

Does this have the potential to silently break my code, if I inadvertently mix character types?

In a word: yes, and there is no workaround that I know of. You'll just see a representation of a pointer value instead of a string of characters, so it's not a potential crash or undefined behaviour, just output that isn't what you want.

Upvotes: 6

Related Questions