c++ - std::bad_cast when using std::basic_istringstream<unsigned short> -


i'm trying process utf-16 string (placed in buffer buf) of std::basic_string , istringstream. exception std::bad_cast occurs in code. there problem code? or gcc's stl cannot handle unsigned int (16 bit) symbols?

const unsigned short * buf; // ... fiilling buf std::basic_string<unsigned short> w(buf); std::basic_istringstream<unsigned short> iss(w);  unsigned int result; try { iss >> result; } catch (std::exception& e) {    const char * c = e.what(); }

the same code std::wstring , std::wistringstream works correctly.

instantiation of iostreams on different character types char , wchar_t rather non-trivial. streams need number of std::locale facets present. without them won't function properly. attempted operation you'd need, @ least:

  • std::ctype<ct>
  • std::numpunct<ct>
  • std::num_get<ct>

where ct stream's character type. last 1 of these should require instantiation others need implemented. of course, need make sure std::locale installed stream either setting global locale or using stream.imbue().

personally, think overall wrong approach, though: characters should converted internal representation when entering system , converted external representation when leaving system (that's purpose of std::codecvt<...> facet). seems, however, lost fight , people feel want mess encodings internally.


Comments

Post a Comment

Popular posts from this blog

java.util.scanner - How to read and add only numbers to array from a text file -

i'm learning java , have question regarding reading file want read numbers file contains strings well. here example of file: 66.56 "3 java 3-43 5-42 2.1 1 and here coding: public class test { public static void main (string [] args){ if (0 < args.length) { file x = new file(args[0]); try{ scanner in = new scanner( new fileinputstream(x)); arraylist<double> test = new arraylist<>(); while(in.hasnext()){ if(in.hasnextdouble()){ double f=in.nextdouble(); test.add(f);} else {in.next();} } catch(ioexception e) { system.err.println("exception during reading: " + e); } } my problem add 66.56,2.1 , 1 doesn't add 3 after "3 or ignores 3-43 , 5-42 can tell me how skip strings , add doubles here? thanks all said 3 ie; "3, 3-43 , 4-42 strings either u read string , split , check number @ " , - or put in space between characters , integers. jvm after compilation tre
Read more

rewrite - Trouble with Wordpress multiple custom querystrings -

i'm working on adding multiple querystring , doesn't seem work. i've found codes seems work others might i'm missing something. i want like: http://mydomain.com/board/?getyear=2013&getsometext2=sometext to http://mydomain.com/board/2013/sometext/ i added code below functions.php file. doesn't seem work should though. this works. echoing querystring gets both variable without problem. http://mydomain.com/board/2013/sometext/ but doesn't. tested querystring vis isset() seems nothing being set/get http://mydomain.com/board/2013/ function add_query_vars($vars) { $vars[] = "getyear"; $vars[] = "getsometext2"; return $vars; } add_filter('query_vars', 'add_query_vars'); function add_rewrite_rules($arules) { $anewrules = array('board/([^/]+)/([^/]+)/?$' => 'index.php?pagename=board&getyear=$matches[1]&getsometext2=$matches[2]'); $arules = $a
Read more

php - Accessing static methods using newly created $obj or using class Name -

see class definition below: i using 5.3.9 version of php class a{ static function ab(){ echo "static function ab<br>"; } public function xy(){ echo "public function xy<br>"; } } $obj = new a(); $obj->ab(); a::ab(); both functions call give same output without error static function ab static function ab how possible static method can called class object? because static method calls using class name only?! now difference between accessing these 2 ways call static method ? referring php.net website declaring class properties or methods static makes them accessible without needing instantiation of class. property declared static can not accessed instantiated class object (though static method can). a big difference is because static methods callable without instance of object created, pseudo-variable $this not available inside method declared static. refer page php.net/manual/en/
Read more