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  • Is there any PDF parser written in objective-c or c?

    - by user549683
    I'm writing a pdf reader iPhone application. I know how to show pdf file in view using CGPDF** classes in iOS. What I want to do now is to search text in pdf file, and highlight the searched text. So, I need a library which can detect what text is in what position. Besides, I want the library able to handle unicode and Chinese characters. I've searched for a few days but still cannot find anything suitable. I've tried xpdf, but it is written in c++. I don't know how to use c++ code in iPhone app. I've also tried http://www.codeproject.com/KB/cpp/ExtractPDFText.aspx but it does not handle Chinese characters. I've tried to code by myself, but the encoding in PDF is really complicated. For example, I don't know what to refer to when I want to decode the text by the following font: 8 0 obj << /Type /Font /Subtype /Type0 /Encoding /Identity-H /BaseFont /RNXJTV+PMingLiU /DescendantFonts [ 157 0 R ] >> endobj 157 0 obj << /Type /Font /Subtype /CIDFontType2 /BaseFont /RNXJTV+PMingLiU /CIDSystemInfo << /Registry (Adobe) /Ordering (CNS1) /Supplement 0 >> /FontDescriptor 158 0 R /W 161 0 R /DW 1000 /CIDToGIDMap 162 0 R >> endobj 158 0 obj << /Type /FontDescriptor /Ascent 801 /CapHeight 711 /Descent -199 /Flags 32 /FontBBox [0 -199 999 801] /FontName /RNXJTV+PMingLiU /ItalicAngle 0 /StemV 0 /Leading 199 /MaxWidth 1000 /XHeight 533 /FontFile2 159 0 R >> endobj

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  • C++ ulong to class method pointer and back

    - by Simone Margaritelli
    Hi guys, I'm using a hash table (source code by Google Inc) to store some method pointers defined as: typedef Object *(Executor::*expression_delegate_t)( vframe_t *, Node * ); Where obviously "Executor" is the class. The function prototype to insert some value to the hash table is: hash_item_t *ht_insert( hash_table_t *ht, ulong key, ulong data ); So basically i'm doing the insert double casting the method pointer: ht_insert( table, ASSIGN, reinterpret_cast<ulong>( (void *)&Executor::onAssign ) ); Where table is defined as a 'hash_table_t *' inside the declaration of the Executor class, ASSIGN is an unsigned long value, and 'onAssign' is the method I have to map. Now, Executor::onAssign is stored as an unsigned long value, its address in memory I think, and I need to cast back the ulong to a method pointer. But this code: hash_item_t* item = ht_find( table, ASSIGN ); expression_delegate_t delegate = reinterpret_cast < expression_delegate_t > (item->data); Gives me the following compilation error : src/executor.cpp:45: error: invalid cast from type ‘ulong’ to type ‘Object* (Executor::*)(vframe_t*, Node*)’ I'm using GCC v4.4.3 on a x86 GNU/Linux machine. Any hints?

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  • c++ creating ambigram from string

    - by mike_hornbeck
    I have a task to implement "void makeAmbigram(char*)" that will print on screen ambigram of latin string or return something like 'ambigram not possible'. Guess it's just about checking if string contains only of SNOXZHI and printing string backwards. Or am I wrong ? I'm a complete noob when dealing with cpp so that's what I've created : #include <iostream> using namespace std; char[]words; char[]reversed; char[] ret_str(char* s) { if(*s != '\0') ret_str(s+1); return s; } void makeAmbigram(char* c) { /* finding chars XIHNOZS and printing ambigram */ } int main() { cin>>words; reversed = ret_str(words); makeAmbigram(reversed); return 0; } I can reverse string but how to check if my reversed string contains only needed chars ? I've found some function but it's hard or even imposible to implement it for greater amount of chars : http://www.java2s.com/Code/C/String/Findcharacterinstringhowtousestrchr.htm

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  • Why does this code leak? (simple codesnippet)

    - by Ela782
    Visual Studio shows me several leaks (a few hundred lines), in total more than a few MB. I traced it down to the following "helloWorld example". The leak disappears if I comment out the H5::DataSet.getSpace() line. #include "stdafx.h" #include <iostream> #include "cpp/H5Cpp.h" int main(int argc, char *argv[]) { _CrtSetDbgFlag ( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF ); // dump leaks at return H5::H5File myfile; try { myfile = H5::H5File("C:\\Users\\yyy\\myfile.h5", H5F_ACC_RDONLY); } catch (H5::Exception& e) { std::string msg( std::string( "Could not open HDF5 file.\n" ) + e.getCDetailMsg() ); throw msg; } H5::Group myGroup = myfile.openGroup("/so/me/group"); H5::DataSet myDS = myGroup.openDataSet("./myfloatvec"); hsize_t dims[1]; //myDS.getSpace().getSimpleExtentDims(dims, NULL); // <-- here's the leak H5::DataSpace dsp = myDS.getSpace(); // The H5::DataSpace seems to leak dsp.getSimpleExtentDims(dims, NULL); //dsp.close(); // <-- doesn't help either std::cout << "Dims: " << dims[0] << std::endl; // <-- Works as expected return 0; } Any help would be appreciated. I've been on this for hours, I hate unclean code...

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  • Having troubles inheriting base class

    - by Nick
    When I inherit the base class, it's telling me there is no such class This is enhanced.h: class enhanced: public changeDispenser // <--------where error is occuring { public: void changeStatus(); // Function: Lets the user know how much of each coin is in the machine enhanced(int); // Constructor // Sets the Dollar amount to what the User wants void changeLoad(int); // Function: Loads what change the user requests into the Coin Machine int dispenseChange(int); // Function: Takes the users amount of cents requests and dispenses it to the user private: int dollar; }; This is enhanced.cpp: #include "enhanced.h" #include <iostream> using namespace std; enhanced::enhanced(int dol) { dollar = dol; } void enhanced::changeStatus() { cout << dollar << " dollars, "; changeDispenser::changeStatus(); } void enhanced::changeLoad(int d) { dollar = dollar + d; //changeDispenser::changeLoad; } This is changeDispenser.h: class changeDispenser { public: void changeStatus(); // Function: Lets the user know how much of each coin is in the machine changeDispenser(int, int, int, int); // Constructor // Sets the Quarters, Dimes, Nickels, and Pennies to what the User wants void changeLoad(int, int, int, int); // Function: Loads what change the user requests into the Coin Machine int dispenseChange(int); // Function: Takes the users amount of cents requests and dispenses it to the user private: int quarter; int dime; int nickel; int penny; }; I didn't include the driver file or the changeDispenser imp file, but in the driver, these are included #include "changeDispenser.h" #include "enhanced.h"

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  • C++ reference variables

    - by avd
    I have these two functions (with Point2D & LineVector (has 2 Point2D member variables) classes and SQUARE macro predefined) inline float distance(const Point2D &p1,const Point2D &p2) { return sqrt(SQUARE(p2.getX()-p1.getX())+SQUARE(p2.getY()-p1.getY())); } inline float maxDistance(const LineVector &lv1,const LineVector &lv2) { return max(distance(lv1.p1,lv2.p2),distance(lv1.p2,lv2.p1)); } but it gives compilation error in maxDistance() function (line 238) saying: /usr/lib/gcc/i686-pc-cygwin/3.4.4/include/c++/bits/stl_iterator_base_types.h: In instantiation of `std::iterator_traits<Point2D>': quadrilateral.cpp:238: instantiated from here /usr/lib/gcc/i686-pc-cygwin/3.4.4/include/c++/bits/stl_iterator_base_types.h:129: error: no type named `iterator_category' in `class Point2D' /usr/lib/gcc/i686-pc-cygwin/3.4.4/include/c++/bits/stl_iterator_base_types.h:130: error: no type named `value_type' in `class Point2D ' /usr/lib/gcc/i686-pc-cygwin/3.4.4/include/c++/bits/stl_iterator_base_types.h:131: error: no type named `difference_type' in `class Point2D' /usr/lib/gcc/i686-pc-cygwin/3.4.4/include/c++/bits/stl_iterator_base_types.h:132: error: no type named `pointer' in `class Point2D' /usr/lib/gcc/i686-pc-cygwin/3.4.4/include/c++/bits/stl_iterator_base_types.h:133: error: no type named `reference' in `class Point2D' Please suggest what is the error?

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  • PC to Macbook Pro Transition - Getting (re)started?

    - by Torus Linvald
    I'm in my second computer science course right now. I've enjoyed programming so far, but really have just scraped my way by. I've not done much programming outside of required class work. For similar reasons, I never really invested in downloading/learning software to help me program (IDE's, editors, compilers, etc). I know it sounds tedious, but my current setup is: notepad++ for coding; Filezilla to transfer .cpp & .h files to school's aludra/unix and compiling; unix tells me where my bugs are and I go back to notepad++ to debug; repeat until done. This isn't fun - and I know it could be easier. But I put it off knowing that I was soon going to switch to a Mac. And, tomorrow, I'm switching. So... How should I set up my Macbook for the best programming experience? What IDEs and editors and debuggers and so on should I download? How will Mac programming differ from PC? I'm open to all ideas and comments, even the most basic. (Background - I'm learning/programming in C++ right now. Next semester, my classes switch to Java. I'm also going to take a class in web development, with HTML/CSS/Javascript/PHP. My new laptop will be a late 2009 Macbook Pro with Leopard, or maybe Snow Leopard. Free would be preferrable for all programs.) Thank you all.

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  • Reverse String Error?

    - by R41nB0w M47r1z
    I am creating this revese string App but i get a error if i include a space in the string ! #include <iostream> #include <string> using namespace std; int main() { int inputa; cout<<"%%%%%%%%%%%%%%%%%%String Reversing App%%%%%%%%%%%%%%%%%%%%%%%%"<<endl<<endl; cout<<"\nEnter 1 to continue and 0 to exit"<<endl<<endl; cin>>inputa; if(inputa!=0) { do { string a,c=""; cout<<"\nEnter the string you want to Reverse : "; cin>>a; for(int x=a.length()-1; x>=0; x--) { c=c+a.substr(x,1); } cout<<"\nThe Reverse String is : "<<c<<endl; cout<<"\nEnter 1 to continue and 0 to exit"<<endl<<endl; cin>>inputa; } while(inputa!=0); } //not my home work } If I type the following string like "abc def" there i get an error . But otherwise it works perfectly ! Is there some mistake with the codes ! I am new to CPP so it would be helpful if you could help me !

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  • C++: Declare static variable in function argument list

    - by MDC
    Is there any way at all in C++ to declare a static variable while passing it to a function? I'm looking to use a macro to expand to the expression passed to the function. The expression needs to declare and initialize a static variable on that particular line (based on the filename and line number using FILE and LINE). int foo(int b) { int c = b + 2; return c; } int main() { int a = 3; a = foo(static int h = 2); //<---- see this! cout << a; return 0; } The problem I'm trying to solve is getting the filename and line number with the FILE and LINE macros provided by the preprocessor, but then creating a lookup table with integer keys leading to the FILE, LINE pairs. For example, the key 89 may map to file foo.cpp, line 20. To get this to work, I'm trying to use local static variables, so that they are initialized only once per line execution. The static variable will be initialized by calling a function that calculates the integer key and adds an entry to the lookup table if it is not there. Right now the program uses a message class to send exception information. I'm writing a macro to wrap this class into a new class: WRAPPER_MACRO(old_class_object) will expand to NewClass(old_class_object, key_value). If I add the static variable declaration as a second line right before this, it should work. The problem is that in most places in the code, the old class object is passed as an argument to a function. So the problem becomes declaring and initializing the static variable somehow with the macro, while keeping the existing function calls.

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  • Qtimer not timing out QT, C++

    - by realz
    Hi, I am learning C++ and using QT. I have a small program in which I am trying to update the text of the PushButton every second. The label being current time. I have a timer that should time out every second, but seems like it never does. here's the code. Header File #ifndef _HELLOFORM_H #define _HELLOFORM_H #include "ui_HelloForm.h" class HelloForm : public QDialog { public: HelloForm(); virtual ~HelloForm(); public slots: void textChanged(const QString& text); void updateCaption(); private: Ui::HelloForm widget; }; #endif /* _HELLOFORM_H */ CPP file #include "HelloForm.h" #include <QTimer> #include <QtGui/QPushButton> #include <QTime> HelloForm::HelloForm(){ widget.setupUi(this); widget.pushButton->setText(QTime::currentTime().toString()); widget.pushButton->setFont(QFont( "Times", 9, QFont::Bold ) ); QTimer *timer = new QTimer(this); connect(timer, SIGNAL(timeout()), SLOT(updateCaption())); timer->start(1000); connect(widget.pushButton, SIGNAL(clicked()), qApp, SLOT(quit()) ); connect(widget.nameEdit, SIGNAL(textChanged(const QString&)), this, SLOT(textChanged(const QString&))); } HelloForm::~HelloForm() { } void HelloForm::textChanged(const QString& text) { if (0 < text.trimmed().length()) { widget.helloEdit->setText("Hello " + text.trimmed() + "!"); } else { widget.helloEdit->clear(); } } void HelloForm::updateCaption() { QString myVar; myVar = QTime::currentTime().toString(); widget.pushButton->setText(myVar); } Any help will be greatly appreciated... The PushButton's text never changes...

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  • Program always returns binary '>>' : no operator found which takes a left-hand operand of type error

    - by Tom Ward
    So I've been set a task to create a temperature converter in C++ using this equation: Celsius = (5/9)*(Fahrenheit – 32) and so far I've come up with this (I've cut out the 10 lines worth of comments from the start so the code posted begins on line 11, if that makes any sense) #include <iostream> #include <string> #include <iomanip> #include <cmath> using namespace std; int main () { float celsius; float farenheit; std::cout << "**************************" << endl; std::cout << "*4001COMP-Lab5-Question 1*" << endl; std::cout << "**************************" << endl << endl; std::cout << "Please enter a temperature in farenheit: "; std::cin >> farenheit >> endl; std::cout << "Temperature (farenheit): " << endl; std::cout << "Temperature (celsius): " << celsius << endl; std::cin.get(); return 0; } Everytime I try to run this program I get a heap of errors with this one appearing every time: 1m:\visual studio 2010\projects\week 5\week 5\main.cpp(26): error C2678: binary '' : no operator found which takes a left-hand operand of type 'std::basic_istream<_Elem,_Traits' (or there is no acceptable conversion) I've tried everything I can think of to get rid of this error but it reappears every time, any idea on how to fix this?

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  • Picture.writeToStream() not writing out all bitmaps

    - by quickdraw mcgraw
    I'm using webview.capturePicture() to create a Picture object that contains all the drawing objects for a webpage. I can successfully render this Picture object to a bitmap using the canvas.drawPicture(picture, dst) with no problems. However when I use picture.writeToStream(fos) to serialize the picture object out to file, and then Picture.createFromStream(fis) to read the data back in and create a new picture object, the resultant bitmap when rendered as above is missing any larger images (anything over around 20KB! by observation). This occurs on all the Android OS platforms that I have tested 1.5, 1.6 and 2.1. Looking at the native code for Skia which is the underlying Android graphics library and the output file produced from the picture.writeToStream() I can see how the file format is constructed. I can see that some of the images in this Skia spool file are not being written out (the larger ones), the code that appears to be the problem is in skBitmap.cpp in the method void SkBitmap::flatten(SkFlattenableWriteBuffer& buffer) const; It writes out the bitmap fWidth, fHeight, fRowBytes, FConfig and isOpaque values but then just writes out SERIALIZE_PIXELTYPE_NONE (0). This means that the spool file does not contain any pixel information about the actual image and therefore cannot restore the picture object correctly. Effectively this renders the writeToStream and createFromStream() APIs useless as they do not reliably store and recreate the picture data. Has anybody else seen this behaviour and if so am I using the API incorrectly, can it be worked around, is there an explanation i.e. incomplete API / bug and if so are there any plans for a fix in a future release of Android? Thanks in advance.

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  • write a program that prompts the user to input five decimal numbers

    - by user312309
    This is the question. write a program that prompts the user to input five decimal numbers. the program should then add the five decimal numbers, convert the sum to the nearest integer,m and print the result. This is what I've gotten so far: // p111n9.cpp : Defines the entry point for the console application. // #include <iostream> using namespace std; double a, b , c , d , e, f; int main(int argc, char* argv[]) { cout << "enter 5 decimals: " << endl; cin >> a >> b >> c >> d >> e; f = a + b + c + d + e; return 0; } Now I just need to convert the sum(f) to the nearest integer, m and print the result. How do I do this?

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  • Passing values for method

    - by Kasun
    I beginner for programming. So can you please show me how to pass values for your compile() method. class CL { private const string clexe = @"cl.exe"; private const string exe = "Test.exe", file = "test.cpp"; private string args; public CL(String[] args) { this.args = String.Join(" ", args); this.args += (args.Length > 0 ? " " : "") + "/Fe" + exe + " " + file; } public Boolean Compile(String content, ref string errors) { //remove any old copies if (File.Exists(exe)) File.Delete(exe); if (File.Exists(file)) File.Delete(file); File.WriteAllText(file, content); Process proc = new Process(); proc.StartInfo.UseShellExecute = false; proc.StartInfo.RedirectStandardOutput = true; proc.StartInfo.RedirectStandardError = true; proc.StartInfo.FileName = clexe; proc.StartInfo.Arguments = this.args; proc.StartInfo.CreateNoWindow = true; proc.Start(); //errors += proc.StandardError.ReadToEnd(); errors += proc.StandardOutput.ReadToEnd(); proc.WaitForExit(); bool success = File.Exists(exe); return success; } }

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  • Resource allocation and automatic deallocation

    - by nabulke
    In my application I got many instances of class CDbaOciNotifier. They all share a pointer to only one instance of class OCIEnv. What I like to achieve is that allocation and deallocation of the resource class OCIEnv will be handled automatically inside class CDbaOciNotifier. The desired behaviour is, with the first instance of class CDbaOciNotifier the environment will be created, after that all following notifiers use that same environment. With the destruction of the last notifier, the environment will be destroyed too (call to custom deleter). What I've got so far (using a static factory method to create notifiers): #pragma once #include <string> #include <memory> #include "boost\noncopyable.hpp" class CDbaOciNotifier : private boost::noncopyable { public: virtual ~CDbaOciNotifier(void); static std::auto_ptr<CDbaOciNotifier> createNotifier(const std::string &tnsName, const std::string &user, const std::string &password); private: CDbaOciNotifier(OCIEnv* envhp); // All notifiers share one environment static OCIEnv* m_ENVHP; // Custom deleter static void freeEnvironment(OCIEnv *env); OCIEnv* m_envhp; }; CPP: #include "DbaOciNotifier.h" using namespace std; OCIEnv* CDbaOciNotifier::m_ENVHP = 0; CDbaOciNotifier::~CDbaOciNotifier(void) { } CDbaOciNotifier::CDbaOciNotifier(OCIEnv* envhp) :m_envhp(envhp) { } void CDbaOciNotifier::freeEnvironment(OCIEnv *env) { OCIHandleFree((dvoid *) env, (ub4) OCI_HTYPE_ENV); *env = null; } auto_ptr<CDbaOciNotifier> CDbaOciNotifier::createNotifier(const string &tnsName, const string &user, const string &password) { if(!m_ENVHP) { OCIEnvCreate( (OCIEnv **) &m_ENVHP, OCI_EVENTS|OCI_OBJECT, (dvoid *)0, (dvoid * (*)(dvoid *, size_t)) 0, (dvoid * (*)(dvoid *, dvoid *, size_t))0, (void (*)(dvoid *, dvoid *)) 0, (size_t) 0, (dvoid **) 0 ); } //shared_ptr<OCIEnv> spEnvhp(m_ENVHP, freeEnvironment); ...got so far... return auto_ptr<CDbaOciNotifier>(new CDbaOciNotifier(m_ENVHP)); } I'd like to avoid counting references (notifiers) myself, and use something like shared_ptr. Do you see an easy solution to my problem?

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  • What to throw in a C++ class wrapping a C library ?

    - by ereOn
    I have to create a set of wrapping C++ classes around an existing C library. For many objects of the C library, the construction is done by calling something like britney_spears* create_britney_spears() and the opposite function void free_britney_spears(britney_spears* brit). If the allocation of a britney_spears fails, create_britney_spears() returns NULL. This is, as far as I know, a very common pattern. Now I want to wrap this inside a C++ class. //britney_spears.hpp class BritneySpears { public: BritneySpears(); private: boost::shared_ptr<britney_spears> m_britney_spears; }; And here is the implementation: // britney_spears.cpp BritneySpears::BritneySpears() : m_britney_spears(create_britney_spears(), free_britney_spears) { if (!m_britney_spears) { // Here I should throw something to abort the construction, but what ??! } } So the question is in the code sample: What should I throw to abort the constructor ? I know I can throw almost anything, but I want to know what is usually done. I have no other information about why the allocation failed. Should I create my own exception class ? Is there a std exception for such cases ? Many thanks.

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  • Exposing a C++ API to C#

    - by Siyfion
    So what I have is a C++ API contained within a *.dll and I want to use a C# application to call methods within the API. So far I have created a C++ / CLR project that includes the native C++ API and managed to create a "bridge" class that looks a bit like the following: ManagedBridge.h namespace ManagedAPIWrapper { public ref class Bridge { public: int bridge_test(void); int bridge_test2(api_struct* temp); } } ManagedBridge.cpp int Bridge::bridge_test(void) { return test(); } int Bridge::bridge_test2(api_struct* temp) { return test2(temp); } I also have a C# application that has a reference to the C++/CLR "Bridge.dll" and then uses the methods contained within. I have a number of problems with this: I can't figure out how to call bridge_test2 within the C# program, as it has no knowledge of what a api_struct actually is. I know that I need to marshal the object somewhere, but do I do it in the C# program or the C++/CLR bridge? This seems like a very long-winded way of exposing all of the methods in the API, is there not an easier way that I'm missing out? (That doesn't use P/Invoke!)

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  • SCons and dependencies for python function generating source

    - by elmo
    I have an input file data, a python function parse and a template. What I am trying to do is use parse function to get dictionary out of data and use that to replace fields in template. Now to make this a bit more generic (I perform the same action in few places) I have defined a custom function to do so. Below is definition of custom builder and values is a dictionary with { 'name': (data_file, parse_function) } (you don't really need to read through this, I simply put it here for completeness). def TOOL_ADD_FILL_TEMPLATE(env): def FillTemplate(env, output, template, values): out = output[0] subs = {} for name, (node, process) in values.iteritems(): def Process(env, target, source): with open( env.GetBuildPath(target[0]), 'w') as out: out.write( process( source[0] ) ) builder = env.Builder( action = Process ) subs[name] = builder( env, env.GetBuildPath(output[0])+'_'+name+'_processed.cpp', node )[0] def Fill(env, target, source): values = dict( (name, n.get_contents()) for name, n in subs.iteritems() ) contents = template[0].get_contents().format( **values ) open( env.GetBuildPath(target[0]), 'w').write( contents ) builder = env.Builder( action = Fill ) builder( env, output[0], template + subs.values() ) return output env.Append(BUILDERS = {'FillTemplate': FillTemplate}) It works fine when it comes to checking if data or template changed. If it did it rebuilds the output. It even works if I edit process function directly. However if my process function looks like this: def process( node ): return subprocess(node) and I edit subprocess the change goes unnoticed. Is there any way to get correct builds without making process functions being always invoked?

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  • C++ Using a class from a header within a class

    - by Kotsuzui
    I'm having a bit of trouble with classes used within classes, from header files. I have an class time in time.h: class Time { private: int hour, second, minute; public: . . . int getHour(int h); etc. setHour(); etc. void print24hour(); // Prints time in 24 hour format } And then, main.cpp: #include "time.h" class Class { private: string name; double grade; Time startTime; Time endTime; public: Class(); ~Class(); void setName(); void setGrade(); etc. } int main() { //Need to print time in 24 hour format, but I don't know how. class[i].startTime.print24(getStartTime()); // ??? I'm rather lost } I get quite a few "hour, second, minute, etc." are private errors, I'm guessing I'm doing something simple in a rather wrong way. Please help.

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  • Using abstract base to implement private parts of a template class?

    - by StackedCrooked
    When using templates to implement mix-ins (as an alternative to multiple inheritance) there is the problem that all code must be in the header file. I'm thinking of using an abstract base class to get around that problem. Here's a code sample: class Widget { public: virtual ~Widget() {} }; // Abstract base class allows to put code in .cpp file. class AbstractDrawable { public: virtual ~AbstractDrawable() = 0; virtual void draw(); virtual int getMinimumSize() const; }; // Drawable mix-in template<class T> class Drawable : public T, public AbstractDrawable { public: virtual ~Drawable() {} virtual void draw() { AbstractDrawable::draw(); } virtual int getMinimumSize() const { return AbstractDrawable::getMinimumSize(); } }; class Image : public Drawable< Widget > { }; int main() { Image i; i.draw(); return 0; } Has anyone walked that road before? Are there any pitfalls that I should be aware of?

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  • Passing array of pointers to another class

    - by user310153
    Hi, I am trying to do the following: in main.cpp: // Create an array of pointers to Block objects Block *blk[64]; for (i=0; i<8; i++) { for (j=0; j<8; j++) { int x_low = i*80; int y_low = j*45; blk[j*8+i] = new Block(30, x_low+40.0f, y_low+7.5f, &b); } } And then I am trying to pass it to the graphics object I have created: Graphics g(640, 480, &b, &p, blk[0], number_of_blocks); the graphics constructor looks like: Graphics::Graphics(int width, int height, Ball *b, Paddle *p, Block *blk, int number_of_blocks) { if I look at what is contained in the array from the graphics object, only the first item exists and then all the other items are in hyperspace: for (int i=0; i<64; i++) { printf("for block %d, %f, %f ", i, (_blk+(sizeof(_blk)*i))->_x_low, (_blk+(sizeof(_blk)*i))->_y_low); printf("blah %d\n", (_blk+(sizeof(_blk)*i))); } and if I look at the addresses, they are different (6956552 rather than 2280520 when I examine the addresses in the main class using: printf(" blah %d\n", &blk[j*8*i]); I am sure there must be something subtle I am doing wrong as its like I have copied the first item from the blk array to a new address when passed to the graphics object. Does this make sense? Any ideas? Cheers, Scott

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  • Memory fragmentation @ boost::asio ?

    - by Poni
    I'm pretty much stuck with a question I never got an answer for, a question which addresses an extremely important issue; memory fragmentation at boost::asio. Found nothing at the documentation nor here at SO. The functions at boost::asio, for example async_write() & async_read_some() always allocate something. (in my case it's 144 & 96 bytes respectively, in VC9 Debug build). How do I know about it? I connect a client to the "echo server" example provided with this library. I put a breakpoint at "new.cpp" at the code of "operator new(size_t size)". Then I send "123". Breakpoint is hit! Now using the stack trace I can clearly see that the root to the "new" call is coming from the async_write() & async_read_some() calls I make in the function handlers. So memory fragmentation will come sooner or later, thus I can't use ASIO, and I wish I could! Any idea? Any helpful code example?

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  • Qt - 2 QMainWindow glued - Size of Layout

    - by user1773603
    I have a main window that I center this way in main.cpp : int main(int argc, char *argv[]) { QApplication app(argc, argv); QMainWindow *qmain = new QMainWindow; Ui_MainWindow ui; ui.setupUi(qmain); QRect r = qmain->geometry(); r.moveCenter(QApplication::desktop()->availableGeometry().center()); qmain->setGeometry(r); qmain->show(); return app.exec(); } In this "qmain" main window, I can create another QMainWindow and I try to make stick (or glue I don't know how to say) the two windows. Actually, I would like the right-top corner of the first one to be located at the left-top of the second one. For this, I use the following Ui_MainWindow's member function : void Ui_MainWindow::generate_IC() { qmenu = new QMainWindow; DiskMenu = new Ui_DiskGalMenu; DiskMenu->setupUi(qmenu); setInitialDiskMenuPosition(qmenu, this); qmenu->show(); } and the setInitialDiskMenuPosition : void Ui_MainWindow::setInitialDiskMenuPosition(QMainWindow *MainWindow, Ui_MainWindow *parent) { QSize size = parent->widget->size(); QDesktopWidget* desktop = QApplication::desktop(); int width = desktop->width(); int height = desktop->height(); int mw = size.width(); int mh = size.height(); int right = (width/2) + (mw/2); int top = (height/2) - (mh/2); MainWindow->move(right, top); } But the problem is that I don't get exactly what I want since the centralwidget size "parent- widget-size()" only returns the size of the widget and not the whole "qmain" parent window. So I have a light shift because the borders of the "qmain" window are not taken in account like it is shown below : If I could have access to the size of the whole parent window... If anyone could help me

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  • When to use () with classes?

    - by SoulBeaver
    This is really starting to confuse the hell out of me. When do I use them, when don't I? For example I was reading a .cpp on linked lists whose class declaration was: struct CarPart { long PartNumber; char Partname[40]; double UnitPrice; CarPart *next; }; class ListOfParts { int size; public: CarPart *head; ListOfParts(); ~ListOfParts(); const int count() const; void insert( CarPart *item ); CarPart *retrieve( int pos ); }; With this code, why am I allowed to write ListOfParts *pPart = new ListOfParts(); CarPart *pCarPart = new CarPart; Declaring an instance of ListOfParts requires (), but not my CarPart? That's confusing me. When I asked a question before and people told me that such a declaration is a function that returns a ListOfParts object, but not the actual constructor. So I'm guessing this is still something different. What's happening here? PS: Am I correct to assume that the const to the right of count() means I cannot modify any values in count?

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  • Deprecated functions not spotted if using "System::Threading::ThreadState" (and others!) C++ VS2005/

    - by Fishboy
    Hi, I'm facing an issue with c++ on vs2005 and also vs2008... here's how you can reproduce the issue.... create a new (c++) project called 'test' (file|new|project) select "Windows Forms Application" and add the 'stdio.h' include and the code fragment below into the test.cpp source file..... -------------------start of snippet-------------------- #include <stdio.h> ... int main(array<System::String ^> ^args) { int i; System::Threading::ThreadState state; char str[20]; sprintf (str, "%s", "test string"); ... -------------------end of snippet-------------------- If you compile the code as above (you'll have to 'buildall' first), you'll get two warnings about 'i' and 'state' being unreferenced (nothing about sprintf being deprecated). If you comment out "System::Threading :Thread state;", you'll get one warning about 'i' being unreferenced and another warning (C4996) for the 'deprecated' sprintf statement.... This issue also occurs for "System::Windows::Forms::MessageBoxIcon", "System::Base64FormattingOptions" (and perhap all 'enum class' types!) Anyone know of the cause and workaround to the issue demonstrated here ( i have other files that demonstate this issue..). (I had started a thread on msdn, but then found this site! see link below) Visual Studio 2005 has stopped warning about deprecated functions

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