c++ - Make template function for nested container -


i'm trying make generic test function takes container such list, set or vector, , returns nested container: list of lists, set of sets, vector of vectors. non-generic functions this:

vector<vector<string>> test(vector<string>& in_container) {     vector<vector<string>> out_continer;      // out_continer filed using values in_container      return out_continer; }  list<list<int>> test(list<int>& in_container) {     list<list<int>> out_continer;      // out_continer filed using values in_container      return out_continer; }  set<set<float>> test(set<float>& in_container) {     set<set<float>> out_continer;      // out_continer filed using values in_container      return out_continer; }

but dont know how make 1 template test function equivalent these separate test examples.

vector , list (and deque) have identical sets of template parameters , ordinary sequences, can cover them with

template <typename t, typename u, template <typename, typename> class c>   c<c<t, u>, std::allocator<c<t, u>>> test(c<t, u> &in) {   c<c<t, u>, std::allocator<c<t, u>>> out;   // fill here   return out; }  int main()  {   std::vector<int> v;   std::vector<std::vector<int>> vv = test(v);    std::list<int> l;   std::list<std::list<int>> ll = test(l); }

(the code bit convoluted since have specify allocator type outer container explicitly, can improved.)

meanwhile set different kind of container (associative), require dedicated function anyway.


-

Comments

Post a Comment

Popular posts from this blog

OpenCV OpenCL: Convert Mat to Bitmap in JNI Layer for Android -

there several posts converting mat bitmap using utils.mattobitmap() function. i'm assuming function can called in java layer after importing utils class. i want transfer data memory address pointed uint32_t* bmpcontent; in code below. jniexport void jnicall java_com_nod_nodcv_nodcvactivity_runfilter( jnienv *env, jclass clazz, jobject outbmp, jbytearray indata, jint width, jint height, jint choice, jint filter) { int outsz = width*height; int insz = outsz + outsz/2; androidbitmapinfo bmpinfo; if (androidbitmap_getinfo(env, outbmp, &bmpinfo) < 0) { throwjavaexception(env,"gaussianblur","error retrieving bitmap meta data"); return; } if (bmpinfo.format != android_bitmap_format_rgba_8888) { throwjavaexception(env,"gaussianblur","expecting rgba_8888 format"); return; } uint32_t* bmpcontent; if (androidbitmap_lockpixels(env, outbmp,(void**)&bmpcontent)...
Read more

android - org.xmlpull.v1.XmlPullParserException: expected: START_TAG {http://schemas.xmlsoap.org/soap/envelope/}Envelope -

i trying hit soap api in application login purpose , getting above mentioned error , can 1 tell me going wrong , first time soap apis. here code hit soap :- vector<object> args = new vector<object>(); hashtable<string, object> hashtable = new hashtable<string, object>(); hashtable.put("email", "mss.siddhart28@gmail.com"); hashtable.put("password", "siddharth"); args.add(hashtable); soapserializationenvelope envelope = new soapserializationenvelope( soapenvelope.ver11); envelope.dotnet = true; envelope.xsd = soapserializationenvelope.xsd; envelope.enc = soapserializationenvelope.enc; (new marshalhashtable()).register(envelope); httptransportse androidhttptransport = new httptransportse( "http://tempuri.org/", 15000); androidhttptransport.debug = true; string result = ""; try { soapobject request = new soapobject("http:...
Read more

python - How to remove the Xframe Options header in django? -

i have made page has iframe . inside iframe want show multiple different links article facebook, or news, or youtube video or other possible url. but, due xframe header, unable so. referred following link: https://docs.djangoproject.com/en/1.8/ref/clickjacking/ , django xframeoptionsmiddleware (x-frame-options) - allow iframe client ip but didn't help. my settings.py file's middleware_classes is: middleware_classes = ( 'django.contrib.sessions.middleware.sessionmiddleware', 'django.middleware.common.commonmiddleware', 'django.middleware.csrf.csrfviewmiddleware', 'django.contrib.auth.middleware.authenticationmiddleware', 'django.contrib.auth.middleware.sessionauthenticationmiddleware', 'django.contrib.messages.middleware.messagemiddleware', 'django.middleware.clickjacking.xframeoptionsmiddleware', ) from http://django-secure.readthedocs.org/en/latest/middleware.html , found using ...
Read more