class OStringStream

The same as std::ostringstream but appends to a user-specified std::string,

and is faster. It is ~70% faster to create, ~50% faster to write to, and

completely free to extract the result std::string.

std::string s;

OStringStream strm(

&s

);

strm

<

<

42

<

<

' '

<

<

3.14; // appends to `s`

The stream object doesn't have to be named. Starting from C++11 operator

<

<

works with rvalues of std::ostream.

std::string s;

OStringStream(

&s

)

<

<

42

<

<

' '

<

<

3.14; // appends to `s`

OStringStream is faster to create than std::ostringstream but it's still

relatively slow. Avoid creating multiple streams where a single stream will

do.

Creates unnecessary instances of OStringStream: slow.

std::string s;

OStringStream(

&s

)

<

<

42;

OStringStream(

&s

)

<

<

' ';

OStringStream(

&s

)

<

<

3.14;

Creates a single instance of OStringStream and reuses it: fast.

std::string s;

OStringStream strm(

&s

);

strm

<

<

42;

strm

<

<

' ';

strm

<

<

3.14;

Note: flush() has no effect. No reason to call it.