Search Results

Search found 22043 results on 882 pages for 'int ua'.

Page 183/882 | < Previous Page | 179 180 181 182 183 184 185 186 187 188 189 190  | Next Page >

• How to add condition on multiple-join table

  - by Jean-Philippe

  Hi, I have those two tables: client: id (int) #PK name (varchar) client_category: id (int) #PK client_id (int) category (int) Let's say I have those datas: client: {(1, "JP"), (2, "Simon")} client_category: {(1, 1, 1), (2, 1, 2), (3, 1, 3), (4,2,2)} tl;dr client #1 has category 1, 2, 3 and client #2 has only category 2 I am trying to build a query that would allow me to search multiple categories. For example, I would like to search every clients that has at least category 1 and 2 (would return client #1). How can I achieve that? Thanks!

  Read the article

• Which fieldtype is best for storing PRICE values?

  - by BerggreenDK

  Hi there I am wondering whats the best "price field" in MSSQL for a shoplike structure? Looking at this overview: http://www.teratrax.com/sql_guide/data_types/sql_server_data_types.html We have datatypes called money, smallmoney, then we have decimal/numeric and lastly float and real Name, memory/disk-usage and value ranges: Money: 8 bytes (values: -922,337,203,685,477.5808 to +922,337,203,685,477.5807) Smallmoney: 4 bytes (values: -214,748.3648 to +214,748.3647) Decimal: 9 [default, min. 5] bytes (values: -10^38 +1 to 10^38 -1 ) Float: 8 bytes (values: -1.79E+308 to 1.79E+308 ) Real: 4 bytes (values: -3.40E+38 to 3.40E+38 ) My question is: is it really wise to store pricevalues in those types? what about eg. INT? Int: 4 bytes (values: -2,147,483,648 to 2,147,483,647) Lets say a shop uses dollars, they have cents, but I dont see prices being $49.2142342 so the use of a lot of decimals showing cents seems waste of SQL bandwidth. Secondly, most shops wouldn't show any prices near 200.000.000 (not in normal webshops at least... unless someone is trying to sell me a famous tower in Paris) So why not go for an int? An int is fast, its only 4 bytes and you can easily make decimals, by saving values in cents instead of dollars and then divide when you present the values. The other approach would be to use smallmoney which is 4 bytes too, but this will require the math part of the CPU to do the calc, where as Int is integer power... on the downside you will need to divide every single outcome. Are there any "currency" related problems with regionalsettings when using smallmoney/money fields? what will these transfer too in C#/.NET ? Any pros/cons? Go for integer prices or smallmoney or some other? Whats does your experience tell?

  Read the article

• How to treat Base* pointer as Derived<T>* pointer?

  - by dehmann

  I would like to store pointers to a Base class in a vector, but then use them as function arguments where they act as a specific class, see here: #include <iostream> #include <vector> class Base {}; template<class T> class Derived : public Base {}; void Foo(Derived<int>* d) { std::cerr << "Processing int" << std::endl; } void Foo(Derived<double>* d) { std::cerr << "Processing double" << std::endl; } int main() { std::vector<Base*> vec; vec.push_back(new Derived<int>()); vec.push_back(new Derived<double>()); Foo(vec[0]); Foo(vec[1]); delete vec[0]; delete vec[1]; return 0; } This doesn't compile: error: call of overloaded 'Foo(Base*&)' is ambiguous Is it possible to make it work? I need to process the elements of the vector differently, according to their int, double, etc. types.

  Read the article

• C++ Long switch statement or look up with a map?

  - by Rachel

  In my C++ application, I have some values that act as codes to represent other values. To translate the codes, I've been debating between using a switch statement or an stl map. The switch would look something like this: int code; int value; switch(code) { case 1: value = 10; break; case 2: value = 15; break; } The map would be an stl::map<int, int> and translation would be a simple lookup with the code used as the key value. Which one is better/more efficient/cleaner/accepted? Why?

  Read the article

• Why can't I create an array with size determined by a global variable?

  - by ashish yadav

  Why does the array a not get initialized by global variable size? #include<stdio.h> int size=5; int main() { int a[size]={1,2,3,4,5}; printf("%d",a[0]); return 0; } The compilation error is shown as "variable-sized object may not be initialized". According to me the array should get initialized by size.

  Read the article

• How can I detect endianness on a system where all primitive integer sizes are the same?

  - by Joe Wreschnig

  (This question came out of explaining the details of CHAR_BIT, sizeof, and endianness to someone yesterday. It's entirely hypothetical.) Let's say I'm on a platform where CHAR_BIT is 32, so sizeof(char) == sizeof(short) == sizeof(int) == sizeof(long). I believe this is still a standards-conformant environment. The usual way to detect endianness at runtime (because there is no reliable way to do it at compile time) is to make a union { int i, char c[sizeof(int)] } x; x.i = 1 and see whether x.c[0] or x.c[sizeof(int)-1] got set. But that doesn't work on this platform, as I end up with a char[1]. Is there a way to detect whether such a platform is big-endian or little-endian, at runtime? Obviously it doesn't matter inside this hypothetical system, but one can imagine it is writing to a file, or some kind of memory-mapped area, which another machine reads and reconstructs it according to its (saner) memory model.

  Read the article

• C++ multiple definition error

  - by user231536

  Starting with sth's answer to this question: http://stackoverflow.com/questions/3023760/c-template-specialization I was wondering how to resolve multiple definition errors if the following code is put in a header file included multiple times by different .cc files and linked together: template <typename T> class C { static const int K; static ostream& print(ostream& os, const T& t) { return os << t;} }; // general case template <typename T> const int C<T>::K = 1; // specialization template <> const int C<int>::K = 2;

  Read the article

• j2me bluetooth client. Function startInquiry nothing found.

  - by Hugi

  I develop simple j2me bluetooth client and have problem with bluetooth device search. Function startInquiry nothing found. Client : nokia 5220 Server : my pc with bluetooth adapter All bluetooth devices is on. /* * To change this template, choose Tools | Templates * and open the template in the editor. */ import javax.microedition.midlet.*; import javax.bluetooth.*; import java.util.Vector; import javax.microedition.lcdui.*; /** * @author ????????????? */ public class Midlet extends MIDlet implements DiscoveryListener { private static Vector vecDevices=new Vector(); private static String connectionURL=null; private LocalDevice localDevice; private DiscoveryAgent agent; private RemoteDevice remoteDevice; private RemoteDevice[] devList; private Display display; private Form form; public void startApp() { display = Display.getDisplay(this); form = new Form( "Client" ); try { localDevice = LocalDevice.getLocalDevice(); } catch( BluetoothStateException e ) { e.printStackTrace(); } form.append("Address: "+localDevice.getBluetoothAddress()+"\n\n"); form.append("Name: "+localDevice.getFriendlyName()+"\n\n"); try { agent = localDevice.getLocalDevice().getDiscoveryAgent(); form.append("Starting device inquiry... \n\n"); boolean si = agent.startInquiry(DiscoveryAgent.GIAC, this); if ( si ) { form.append("true"); } else { form.append("false"); } } catch( BluetoothStateException e ) { } int deviceCount = vecDevices.size(); if(deviceCount <= 0){ form.append("No Devices Found ."); } else{ //print bluetooth device addresses and names in the format [ No. address (name) ] form.append("Bluetooth Devices: "); for (int i = 0; i < deviceCount; i++) { remoteDevice=(RemoteDevice)vecDevices.elementAt(i); form.append( remoteDevice.getBluetoothAddress() ); } } display.setCurrent(form); } public void pauseApp() { } public void destroyApp(boolean unconditional) { } public void deviceDiscovered(RemoteDevice btDevice, DeviceClass cod) { //add the device to the vector if(!vecDevices.contains(btDevice)){ vecDevices.addElement(btDevice); } } public void inquiryCompleted(int discType) { } //implement this method since services are not being discovered public void servicesDiscovered(int transID, ServiceRecord[] servRecord) { if(servRecord!=null && servRecord.length>0){ connectionURL=servRecord[0].getConnectionURL(0,false); } } //implement this method since services are not being discovered public void serviceSearchCompleted(int transID, int respCode) { } }

  Read the article

• Compatible types and structures in C

  - by Oli Charlesworth

  I have the following code: int main(void) { struct { int x; } a, b; struct { int x; } c; struct { int x; } *p; b = a; /* OK */ c = a; /* Doesn't work */ p = &a; /* Doesn't work */ return 0; } which fails to compile under GCC (3.4.6), with the following error: test.c:8: error: incompatible types in assignment test.c:9: warning: assignment from incompatible pointer type Now, from what I understand (admittedly from the C99 standard), is that a and c should be compatible types, as they fulfill all the criteria in section 6.2.7, paragraph 1. I've tried compiling with std=c99, to no avail. Presumably my interpretation of the standard is wrong?

  Read the article

• Best solution for an StringToInt function in C#

  - by StefanE

  Hi, I were asked to do an StringToInt / Int.parse function on the white board in an job interview last week and did not perform very good but I came up with some sort of solution. Later when back home I made one in Visual Studion and I wonder if there are any better solution than mine below. Have not bothred with any more error handling except checking that the string only contains digits. private int StrToInt(string tmpString) { int tmpResult = 0; System.Text.Encoding ascii = System.Text.Encoding.ASCII; byte[] tmpByte = ascii.GetBytes(tmpString); for (int i = 0; i <= tmpString.Length-1; i++) { // Check whatever the Character is an valid digit if (tmpByte[i] > 47 && tmpByte[i] <= 58) // Here I'm using the lenght-1 of the string to set the power and multiply this to the value tmpResult += (tmpByte[i] - 48) * ((int)Math.Pow(10, (tmpString.Length-i)-1)); else throw new Exception("Non valid character in string"); } return tmpResult; }

  Read the article

• How can I return a Dictionary from F# to C# without having to include FSharp.Core?

  - by Benjol

  I'm trying to return a IDictionary<int,int> (created with dict tuplist) from F# to C#, but it says that I must include a reference to FSharp.Core because of System.Collections.IStructuralEquatable. I've tried returning a Dictionary<_,_>(dict tuplist), but that doesn't make any difference. I even tried Dictionary<_,_>(dict tuplist, HashIdentity.Reference), but that says that int is a struct...

  Read the article

• Variable might not have been initialized error

  - by David

  When i try to compile this: public static Rand searchCount (int[] x) { int a ; int b ; ... for (int l= 0; l<x.length; l++) { if (x[l] == 0) a++ ; else if (x[l] == 1) b++ ; } ... } I get these errors: Rand.java:72: variable a might not have been initialized a++ ; ^ Rand.java:74: variable b might not have been initialized b++ ; ^ 2 errors it seems to me that i initialized them at the top of the method. Whats going wrong?

  Read the article

• pass array by reference in c

  - by Yassir

  How can I pass an array of struct by reference ? example : struct Coordinate { int X; int Y; }; SomeMethod(Coordinate *Coordinates[]){ //Do Something with the array } int main(){ Coordinate Coordinates[10]; SomeMethod(&Coordinates); }

  Read the article

• Pythagoras triangle

  - by Gogolo

  I would like to ask you about this programing part, is it everything ok? the task was: Write the pseudocode or flow diagram and code for the theorem of Pythagoras - for right-angle triangle with three ribs (a, b, and c) of type integer int KendiA = 0; int KendiB = 0; int H = 0; string Trekendeshi = null; int gjetja = 0; for (KendiA = 1; KendiA <= 15; KendiA++) { for (KendiB = 1; KendiB <= 15; KendiB++) { for (H = 1; H <= 30; H++) { if ((Math.Pow(KendiA, 2) + Math.Pow(KendiB, 2) == Math.Pow(H, 2))) { gjetja = gjetja + 1; Trekendeshi = gjetja + "\t" + KendiA + "\t" + KendiB + "\t" + H; Console.WriteLine(Trekendeshi); } } } }

  Read the article

• Copy constructor called even when returning by reference?

  - by Johnyy

  Hi, I am testing the return of local objects by reference. My original test went well but something else happens unexpected. #include <iostream> using namespace std; class MyInt { public: MyInt(int i){ value = new int(i); } ~MyInt(){ delete value; } int getValue(){ return *value; } MyInt(const MyInt &b){ cout<<"Copy"<<endl; } private: int* value; }; MyInt& returnref(){ MyInt a(10); cout<<"Returning from returnref()"<<endl; return a; } int main(){ MyInt a = returnref(); cout<<a.getValue()<<endl; return 0; } My console prints "Returning from ..." then "Copy" then a random value. My understanding of pass by reference is that it does not need to make any copy. Why is it not doing what I expected?

  Read the article

• Avoid warning 'Unreferenced Formal Parameter'

  - by bdhar

  I have a super class like this: class Parent { public: virtual void Function(int param); }; void Parent::Function(int param) { std::cout << param << std::endl; } ..and a sub-class like this: class Child : public Parent { public: void Function(int param); }; void Child::Function(int param) { ;//Do nothing } When I compile the sub-class .cpp file, I get this error warning C4100: 'param' : unreferenced formal parameter As a practise, we used to treat warnings as errors. How to avoid the above warning? Thanks.

  Read the article

• Prevent Negative numbers for Age without using client side validation.

  - by Deepak

  Hi People, I have an issue in Core java. Consider the Employee class having an attribute called age. class Employee{ private int age; public void setAge(int age); } My question is how do i restrict/prevent setAge(int age) method such that it accepts only positive numbers and it should not allow negative numbers, Note: This has to be done without using client side validation.how do i achieve it using Java/server side Validation only.The validation for age attribute should be handled such that no exception is thrown

  Read the article

• Specifying character

  - by danutenshu

  So below I have a code in C++ that is supposed to invert the arguments in a vector, but not the sequence. I have listed my problems as sidenotes in the code below. The invert function is supposed to invert each argument, and then the main function just outputs the inverted words in same order For instance, program("one two three four")=ruof eerth owt eno #include <iostream> #include <string> using namespace std; int invert(string normal) { string inverted; for (int num=normal.size()-1; num>=0; num--) { inverted.append(normal[num]); //I don't know how to get each character //I need another command for append } return **inverted**; <---- } int main(int argc, char* argv[]) { string text; for (int a=1; a<argc; a++) { text.append(invert(argv[a])); //Can't run the invert function text.append(" "); } cout << text << endl; return 0; }

  Read the article

• alternatyve in php (from java)

  - by Valdas

  I have some problem have class in java. But now need have in php. it's possible rewrite? Code: public class RealityStream { public RealityStream(byte abyte0[]) { m_dstream = null; m_dstream = new DataInputStream(new ByteArrayInputStream(abyte0)); } public int available() throws IOException { return m_dstream.available(); } public float readFloat() throws IOException { byte byte0 = m_dstream.readByte(); byte byte1 = m_dstream.readByte(); byte byte2 = m_dstream.readByte(); byte byte3 = m_dstream.readByte(); int i = (byte3 & 0xff) << 24 | (byte2 & 0xff) << 16 | (byte1 & 0xff) << 8 | byte0 & 0xff; return Float.intBitsToFloat(i); } public int readInt() throws IOException { byte byte0 = m_dstream.readByte(); byte byte1 = m_dstream.readByte(); byte byte2 = m_dstream.readByte(); byte byte3 = m_dstream.readByte(); return (byte3 & 0xff) << 24 | (byte2 & 0xff) << 16 | (byte1 & 0xff) << 8 | byte0 & 0xff; } public int readShort() throws IOException { byte byte0 = m_dstream.readByte(); byte byte1 = m_dstream.readByte(); return byte1 << 8 | byte0 & 0xff; } public int readUnsignedChar() throws IOException { return m_dstream.readUnsignedByte(); } private DataInputStream m_dstream; } very need. very thaks.

  Read the article

• Why won't this compile and how can it be implemented so that it does?

  - by George Edison

  Here is some C++ code I'm playing around with: #include <iostream> #include <vector> #define IN , #define FOREACH(x,y) for(unsigned int i=0;i<y.size();i++) { x=y[i]; #define ENDFOREACH } using namespace std; int main() { vector<int> ints; ints.push_back(3); ints.push_back(4); ints.push_back(5); ints.push_back(6); FOREACH(int item IN ints) cout << item; ENDFOREACH return 0; } However, I get an error: macro "FOREACH" requires 2 arguments, but only 1 given The code compiles if I change the IN to a comma. How can I get the IN to take the place of a comma?

  Read the article

• Creating a custom module for Orchard

  - by Moran Monovich

  I created a custom module using this guide from Orchard documentation, but for some reason I can't see the fields in the content type when I want to create a new one. this is my model: public class CustomerPartRecord : ContentPartRecord { public virtual string FirstName { get; set; } public virtual string LastName { get; set; } public virtual int PhoneNumber { get; set; } public virtual string Address { get; set; } public virtual string Profession { get; set; } public virtual string ProDescription { get; set; } public virtual int Hours { get; set; } } public class CustomerPart : ContentPart<CustomerPartRecord> { [Required(ErrorMessage="you must enter your first name")] [StringLength(200)] public string FirstName { get { return Record.FirstName; } set { Record.FirstName = value; } } [Required(ErrorMessage = "you must enter your last name")] [StringLength(200)] public string LastName { get { return Record.LastName; } set { Record.LastName = value; } } [Required(ErrorMessage = "you must enter your phone number")] [DataType(DataType.PhoneNumber)] public int PhoneNumber { get { return Record.PhoneNumber; } set { Record.PhoneNumber = value; } } [StringLength(200)] public string Address { get { return Record.Address; } set { Record.Address = value; } } [Required(ErrorMessage = "you must enter your profession")] [StringLength(200)] public string Profession { get { return Record.Profession; } set { Record.Profession = value; } } [StringLength(500)] public string ProDescription { get { return Record.ProDescription; } set { Record.ProDescription = value; } } [Required(ErrorMessage = "you must enter your hours")] public int Hours { get { return Record.Hours; } set { Record.Hours = value; } } } this is the Handler: class CustomerHandler : ContentHandler { public CustomerHandler(IRepository<CustomerPartRecord> repository) { Filters.Add(StorageFilter.For(repository)); } } the Driver: class CustomerDriver : ContentPartDriver<CustomerPart> { protected override DriverResult Display(CustomerPart part, string displayType, dynamic shapeHelper) { return ContentShape("Parts_Customer", () => shapeHelper.Parts_BankCustomer( FirstName: part.FirstName, LastName: part.LastName, PhoneNumber: part.PhoneNumber, Address: part.Address, Profession: part.Profession, ProDescription: part.ProDescription, Hours: part.Hours)); } //GET protected override DriverResult Editor(CustomerPart part, dynamic shapeHelper) { return ContentShape("Parts_Customer", () => shapeHelper.EditorTemplate( TemplateName:"Parts/Customer", Model: part, Prefix: Prefix)); } //POST protected override DriverResult Editor(CustomerPart part, IUpdateModel updater, dynamic shapeHelper) { updater.TryUpdateModel(part, Prefix, null, null); return Editor(part, shapeHelper); } the migration: public class Migrations : DataMigrationImpl { public int Create() { // Creating table CustomerPartRecord SchemaBuilder.CreateTable("CustomerPartRecord", table => table .ContentPartRecord() .Column("FirstName", DbType.String) .Column("LastName", DbType.String) .Column("PhoneNumber", DbType.Int32) .Column("Address", DbType.String) .Column("Profession", DbType.String) .Column("ProDescription", DbType.String) .Column("Hours", DbType.Int32) ); return 1; } public int UpdateFrom1() { ContentDefinitionManager.AlterPartDefinition("CustomerPart", builder => builder.Attachable()); return 2; } public int UpdateFrom2() { ContentDefinitionManager.AlterTypeDefinition("Customer", cfg => cfg .WithPart("CommonPart") .WithPart("RoutePart") .WithPart("BodyPart") .WithPart("CustomerPart") .WithPart("CommentsPart") .WithPart("TagsPart") .WithPart("LocalizationPart") .Creatable() .Indexed()); return 3; } } Can someone please tell me if I am missing something?

  Read the article

• quick java question

  - by j-unit-122

  private static char[] quicksort (char[] array , int left , int right) { if (left < right) { int p = partition(array , left, right); quicksort(array, left, p - 1 ); quicksort(array, p + 1 , right); } for (char i : array) System.out.print(i + ” ”); System.out.println(); return array; } private static int partition(char[] a, int left, int right) { char p = a[left]; int l = left + 1, r = right; while (l < r) { while (l < right && a[l] < p) l++; while (r > left && a[r] >= p) r--; if (l < r) { char temp = a[l]; a[l] = a[r]; a[r] = temp; } } a[left] = a[r]; a[r] = p; return r; } } hi guys just a quick question regarding the above coding, i know that the above coding returns the following B I G C O M P U T E R B C E G I M P U T O R B C E G I M P U T O R B C E G I M P U T O R B C E G I M P U T O R B C E G I M O P T U R B C E G I M O P R T U B C E G I M O P R T U B C E G I M O P R T U B C E G I M O P R T U B C E G I M O P R T U B C E G I M O P R T U B C E G I M O P R T U when the sequence BIGCOMPUTER is used but my question is can someone explain to me what is happening in the code and how? i know abit about the quick-sort algorithm but it doesnt seem to be the same in the above example.

  Read the article

• Why wont my while loop wont take new input (c++)

  - by Van

  I've written a program to get a string input from a user and parse it into tokens and move a robot according to the input. My problem is trying to issue more than one command. The code looks like: void Navigator::manualDrive() { const int bufSize = 42; char uinput[bufSize]; char delim[] = " "; char *token; while(true) { Navigator::parseInstruction(uinput); } } /* parseInstruction(char *c) -- parses cstring instructions received * and moves robot accordingly */ void Navigator::parseInstruction(char * c) { const int bufSize = 42; char uinput[bufSize]; char delim[] = " "; char *token; cout << "Enter your directions below: \n"; cin.ignore(); cin.getline (uinput, bufSize); token=strtok(uinput, delim); if(strcmp("forward", token) == 0) { int inches; token = strtok(NULL, delim); inches = atoi (token); Navigator::travel(inches); } if(strcmp("back",token) == 0) { int inches; token = strtok(NULL, delim); inches = atoi (token); double value = fabs(0.0735 * fabs(inches) - 0.0550); myRobot.backward(1/*speed*/, value/*time*/); } if(strcmp("turn",token) == 0) { int degrees; token = strtok(NULL, delim); if(strcmp("left",token) == 0) { token = strtok(uinput, delim); degrees = atoi (token); double value = fabs(0.0041 * degrees - 0.0523); myRobot.turnLeft(1/*speed*/, value/*time*/); } } if(strcmp("turn",token) == 0) { int degrees; token = strtok(NULL, delim); if(strcmp("right",token) == 0) { token = strtok(uinput, delim); degrees = atoi (token); double value = fabs(0.0041 * degrees - 0.0523); myRobot.turnRight(1/*speed*/, value/*time*/); } } if(strcmp("stop",token) == 0) { myRobot.motors(0,0); } } In the function manualDrive I have a while loop calling the function parseInstruction infinitely. The program outputs "Enter your directions below: " When I give the program instructions it executes them, and then it outputs "enter your directions below: " again and when I input my directions again it does not execute them and outputs "Enter your directions below: " instead. I'm sure this is a very simple fix I'm just very new to c++. So if you could please help me out and tell me why the program only takes the first set of directions. thanks

  Read the article

• Passing a Structure containing an array of String and an array of Integer into a C++ DLL

  - by DanJunior

  I'm having problems with marshaling in VB.NET to C++, here's the code : In the C++ DLL : struct APP_PARAM { int numData; LPCSTR *text; int *values; }; int App::StartApp(APP_PARAM params) { for (int i = 0; i < numLines; i++) { OutputDebugString(params.text[i]); } } In VB.NET : <StructLayoutAttribute(LayoutKind.Sequential)> _ Public Structure APP_PARAM Public numData As Integer Public text As System.IntPtr Public values As System.IntPtr End Structure Declare Function StartApp Lib "AppSupport.dll" (ByVal params As APP_PARAM) As Integer Sub Main() Dim params As APP_PARAM params.numData = 3 Dim text As String() = {"A", "B", "C"} Dim textHandle As GCHandle = GCHandle.Alloc(text) params.text = GCHandle.ToIntPtr(textHandle) Dim values As Integer() = {10, 20, 30} Dim valuesHandle As GCHandle = GCHandle.Alloc(values) params.values = GCHandle.ToIntPtr(heightHandle) StartApp(params) textHandle.Free() valuesHandle.Free() End Sub I checked the C++ side, the output from the OutputDebugString is garbage, the text array contains random characters. What is the correct way to do this?

  Read the article

• What's the C strategy to "imitate" a C++ template ?

  - by Andrei Ciobanu

  After reading some examples on stackoverflow, and following some of the answers for my previous questions (1), I've eventually come with a "strategy" for this. I've come to this: 1) Have a declare section in the .h file. Here I will define the data-structure, and the accesing interface. Eg.: /** * LIST DECLARATION. (DOUBLE LINKED LIST) */ #define NM_TEMPLATE_DECLARE_LIST(type) \ typedef struct nm_list_elem_##type##_s { \ type data; \ struct nm_list_elem_##type##_s *next; \ struct nm_list_elem_##type##_s *prev; \ } nm_list_elem_##type ; \ typedef struct nm_list_##type##_s { \ unsigned int size; \ nm_list_elem_##type *head; \ nm_list_elem_##type *tail; \ int (*cmp)(const type e1, const type e2); \ } nm_list_##type ; \ \ nm_list_##type *nm_list_new_##type##_(int (*cmp)(const type e1, \ const type e2)); \ \ (...other functions ...) 2) Wrap the functions in the interface inside MACROS: /** * LIST INTERFACE */ #define nm_list(type) \ nm_list_##type #define nm_list_elem(type) \ nm_list_elem_##type #define nm_list_new(type,cmp) \ nm_list_new_##type##_(cmp) #define nm_list_delete(type, list, dst) \ nm_list_delete_##type##_(list, dst) #define nm_list_ins_next(type,list, elem, data) \ nm_list_ins_next_##type##_(list, elem, data) (...others...) 3) Implement the functions: /** * LIST FUNCTION DEFINITIONS */ #define NM_TEMPLATE_DEFINE_LIST(type) \ nm_list_##type *nm_list_new_##type##_(int (*cmp)(const type e1, \ const type e2)) \ {\ nm_list_##type *list = NULL; \ list = nm_alloc(sizeof(*list)); \ list->size = 0; \ list->head = NULL; \ list->tail = NULL; \ list->cmp = cmp; \ }\ void nm_list_delete_##type##_(nm_list_##type *list, \ void (*destructor)(nm_list_elem_##type elem)) \ { \ type data; \ while(nm_list_size(list)){ \ data = nm_list_rem_##type(list, tail); \ if(destructor){ \ destructor(data); \ } \ } \ nm_free(list); \ } \ (...others...) In order to use those constructs, I have to create two files (let's call them templates.c and templates.h) . In templates.h I will have to NM_TEMPLATE_DECLARE_LIST(int), NM_TEMPLATE_DECLARE_LIST(double) , while in templates.c I will need to NM_TEMPLATE_DEFINE_LIST(int) , NM_TEMPLATE_DEFINE_LIST(double) , in order to have the code behind a list of ints, doubles and so on, generated. By following this strategy I will have to keep all my "template" declarations in two files, and in the same time, I will need to include templates.h whenever I need the data structures. It's a very "centralized" solution. Do you know other strategy in order to "imitate" (at some point) templates in C++ ? Do you know a way to improve this strategy, in order to keep things in more decentralized manner, so that I won't need the two files: templates.c and templates.h ?

  Read the article

< Previous Page | 179 180 181 182 183 184 185 186 187 188 189 190  | Next Page >