using embedded stringstream on a single line. - Boost-users - lists.preview.boost.org

newer
[boost.function] conflict with...

using embedded stringstream on a single line.

older
Feedback on units use

Avi Bahra

26 Aug 2009 26 Aug '09

3:13 p.m.

Is there anything in boost/design pattern that can help with following: std::stringstream ss; ss << "SUBMIT: Task(" << absPath << ") "; log( Log::DBG, ss ); The code I am working on does this all over the place, what I would like is : log( Log::DBG, "SUBMIT: Task(" << absPath << ") " ); Best regards, Ta, Avi

Attachments:

attachment.html (text/html — 479 bytes)

Reply

Sign in to reply online Use email software

Show replies by date

Robert Jones

26 Aug 26 Aug

3:22 p.m.

On Wed, Aug 26, 2009 at 4:13 PM, Avi Bahra wrote:

Is there anything in boost/design pattern that can help with following:

std::stringstream ss; ss << "SUBMIT: Task(" << absPath << ") "; log( Log::DBG, ss );

The code I am working on does this all over the place, what I would like is :

log( Log::DBG, "SUBMIT: Task(" << absPath << ") " );

Well, you could have a look at Boost.Format. It gets you part way there, but you'd still have a std::string rather than std::stringstream. Maybe your log function has a std::string overload? - Rob.

Reply

Sign in to reply online Use email software

Stuart Dootson

3:26 p.m.

On Wed, Aug 26, 2009 at 4:13 PM, Avi Bahra wrote:

Is there anything in boost/design pattern that can help with following:

std::stringstream ss; ss << "SUBMIT: Task(" << absPath << ") "; log( Log::DBG, ss );

The code I am working on does this all over the place, what I would like is :

log( Log::DBG, "SUBMIT: Task(" << absPath << ") " );

Best regards, Ta, Avi

Slightly different, but how about Boost.Format? log( Log::DBG, str(boost::format("SUBMIT: Task( %s) ")%absPath) ); Internally, it uses streams, so your ostream inserters for custom types will get used, I believe. Stuart Dootson

Reply

Sign in to reply online Use email software

Eric MALENFANT

5:13 p.m.

Avi Bahra wrote:

Is there anything in boost/design pattern that can help with following:

std::stringstream ss; ss << "SUBMIT: Task(" << absPath << ") "; log( Log::DBG, ss );

The code I am working on does this all over the place, what I would like is :

log( Log::DBG, "SUBMIT: Task(" << absPath << ") " );

Something simple would be to use lexical_cast (assuming your log() function has an overload accepting strings): log(Log::DBG, "Submit: Task(" + boost::lexical_caststd::string(absPath) + ")"); Alternatively, to get a nicer interface for the caller, the log() function could be templatized and take care of the streaming. Something like: template void log(Log::Level l, const Arg1T& arg1 = None(), const Arg2T& arg2 = None(), const Arg3T& arg3 = None()) { std::stringstream ss; ss << arg1 << arg2 << arg3; log(l, ss); } (Assuming a do-nothing operator<<(ostream&, const None&)) used as: log(Log::DBG, "Submit: Task(", absPath, ")");

Reply

Sign in to reply online Use email software

Nat Goodspeed

27 Aug 27 Aug

11:31 p.m.

Avi Bahra wrote:

Is there anything in boost/design pattern that can help with following:

std::stringstream ss; ss << "SUBMIT: Task(" << absPath << ") "; log( Log::DBG, ss );

The code I am working on does this all over the place, what I would like is :

log( Log::DBG, "SUBMIT: Task(" << absPath << ") " );

My colleague came up with a really cute mechanism: #include <sstream> #include // helper, see STRINGIZE() macro template <typename Functor> std::string stringize_f(Functor const & f) { std::ostringstream out; f(out); return out.str(); } #define STRINGIZE(EXPRESSION) \ (stringize_f(boost::lambda::_1 << EXPRESSION)) You'd use it something like: log(Log::DBG, STRINGIZE("SUBMIT: Task(" << absPath << ") ")); Or you could wrap your log() function in a LOG() macro: #define LOG(level, EXPRESSION) \ log(level, STRINGIZE(EXPRESSION)) which would permit your original syntax, using LOG() instead of log().

Reply

Sign in to reply online Use email software

5727

Age (days ago)

5728

Last active (days ago)

Download

4 comments

5 participants

tags

participants (5)

Avi Bahra
Eric MALENFANT
Nat Goodspeed
Robert Jones
Stuart Dootson