Questions about C++, a statically typed, free-form, multi-paradigm, compiled, general-purpose programming language.

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1
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3answers
325 views

C++: Metaprogramming with a compiler API rather than with C++ features

This started out as a SO question but I realized that it is quite unconventional and based on the actual description on the websites, it might be better suited to programmers.se since the question has ...
1
vote
1answer
301 views

Binary Tree/Knowledge Base design C++

Currently I have a binary tree template setup where my main is using it with strings to make a question/answer game. I'm using a knowledge base that works as an interface to the binary tree that main ...
0
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1answer
93 views

Organise C++ classes around SQL database

My question is about how best to organize C++ classes around a database model, and I understand this may appear very elementary. The software I propose to create will do the following. It is intended ...
-1
votes
0answers
60 views

Sharing dynamically allocated arrays between C++ source files [migrated]

I am trying to compile a code with two (more actually, but that is not important) source codes. In one of them I declared a variable size array like this: const int number_of_equidistant = ...
0
votes
1answer
159 views

GUI code implementation for specific Window/Form class

Terminology Element/Form Element -> Fields such as text list, combo_boxes, push buttons, etc. Problem I have a program that is basically a fat client that interfaces into a system that keeps track ...
0
votes
3answers
264 views

Good 'real life' example of operator overloading C++ [closed]

What are examples of classes to use operator overloading on in C++? All the examples and tutorials I can find on the net use non-sensical classes/objects (foo/bar, one or two integers..) What are the ...
0
votes
2answers
133 views

How to organise and label methods, intended for debug?

I have a class System, which uses a bunch of other classes, to achieve a complex signal processing. In debugging System, one needs to observe the output signal for patterns. This is not achievable by ...
0
votes
0answers
43 views

c++ coding practice class vs. “free” functions [duplicate]

I am currently writing my first bigger project in c++. Its basic linear algebra. I am aware that boost libraries and others exist, but for various reasons I need to write my own. Purpose of the ...
0
votes
0answers
83 views

c++ understanding size_t behaviour for vector creation [migrated]

this is a folow up to this c++ coding practice class vs. "free" functions question I posted a few day ago. In short, the idea is to create a custom vector class for statistical data ...
1
vote
4answers
392 views

How to work around Java's lack of pointers to pointers when working with linked data structures? [closed]

I've learned from a textbook how to implement binary search trees recursively in Java, and am working on implementing them nonrecursively. I've found a simple and elegant way to implement an insert ...
61
votes
6answers
38k views

When do you use float and when do you use double

Frequently in my programming experience I need to make a decision whether I should use float or double for my real numbers. Sometimes I go for float, sometimes I go for double, but really this feels ...
28
votes
5answers
9k views

Why is there no 'finally' construct in C++?

Exception handling in C++ is limited to try/throw/catch. Unlike Object Pascal, Java, C# and Python, even in C++ 11, the finally construct has not been implemented. I have seen an awful lot of C++ ...
3
votes
4answers
170 views

Storing a pointer to an argument passed by (non-const) reference

When designing an interface for passing objects which are meant to be stored for later use and which should not be 'null', I am always a bit uncertain if the argument should be passed by reference or ...
1
vote
3answers
248 views

Application qos involving priority and bandwidth

Our manager wants us to do applicaiton qos which is quite different from the well-known system qos. We have many services of three types, they have priorites, the manager wants to suspend low priority ...
0
votes
2answers
130 views

Can I create a type, typedef or using statement that results in a different type if instantiated a second time or more?

Suppose I have a class that evaluates some computationally intensive function: class Value { private: int eval() { mCached = ExpensiveOperation(); return mCached; } static int ...
2
votes
1answer
151 views

How do multiple levels of inheritance affect virtual function call overhead in C++?

I am considering using a class hierarchy with more than a single level of inheritance, where virtual member functions form a "chain", for example: struct Base { virtual void foo(); }; struct D1 : ...
0
votes
0answers
40 views

API for accessing CTS and DSR signals of serial port

I'm trying to improve another abstraction of the serial port. The project involved often needs to check one of the single control signals CTS and DSR. This is currently done by a call to ...
22
votes
10answers
7k views

Why are pointers not recommended when coding with C++

I read from somewhere that when using C++ it is recommended not to use pointers. Why is pointers such a bad idea when you are using C++. For C programmers that are used to using pointers, what is the ...
8
votes
7answers
297 views

How does a variable introduce state?

I was reading the "C++ Coding Standards" and this line was there: Variables introduce state, and you should have to deal with as little state as possible, with lifetimes as short as possible. ...
0
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0answers
4 views

error LNK2019: unresolved external symbol? [migrated]

Firstly, I am beginner in c++ and Visual C++ (but not OOP). I am now trying to import Excel data to my data structure. What I have done is creating the structure(as class) in dataStructures.cpp along ...
6
votes
4answers
461 views

Undefined behavior, in principle

Whether in C or C++, I think that this illegal program, whose behavior according to the C or C++ standard is undefined, is interesting: #include <stdio.h> int foo() { int a; const int ...
3
votes
2answers
251 views

Does ODBC require any run-time software beyond an .exe file to run against MySQL and ORACLE SQL? [closed]

I'm writing a software [under Windows] in C++ which later needs to be able to connect to both MySQL and ORACLE SQL. Now the software needs to be as simple for the user as possible. Now I'm ...
-1
votes
1answer
98 views

What are guidelines for a Win/Mac/Linux C++ source tree? [closed]

I'm learning C++ (C++11), specifically for cross platform game development using SDL. on Windows, I use Visual Studio 2012 (Considering buying '14' once it's out), on Mac OS X and iOS I'll be using ...
1
vote
4answers
464 views

c++ coding practice class vs. “free” functions

I am currently writing my first bigger project in c++. Its basic linear algebra. I am aware that boost libraries and others exist, but for various reasons I need to write my own. Purpose of the ...
1
vote
1answer
86 views

Standardization and official guidelines for C++ template parameter naming [closed]

What are some explicit and official guidelines or standards for template parameter naming in C++? I've done something like this in the past: template<typename TContainer, typename TKey> void ...
1
vote
3answers
172 views

Is it bad practice to use Inheritance to associate methods with a basic container?

Basically, I have code that looks like this. It's a typedef and a set of methods that revolve around that typedef. class foo { // Foo stuff... // Registration Stuff private: ...
4
votes
2answers
272 views

dealing with a very large state machine in a class

I am currently implementing a class for a network protocol. The protocol uses a quite complex and extensive finite state machine. A pair of an event plus a state is mapped to a function, which does ...
1
vote
1answer
129 views

C++ : Association, Aggregation and Composition [closed]

I'm beginning to study OOAD and I'm having difficulty finding a C++ code example that'd illustrate how Association, Aggregation and Composition are implemented programmatically. (There are several ...
82
votes
11answers
21k views

What backs up the claim that C++ can be faster than a JVM or CLR with JIT? [closed]

A reoccurring theme on SE I've noticed in many questions is the ongoing argument that C++ is faster and/or more efficient than higher level languages like Java. The counter-argument is that modern JVM ...
1
vote
2answers
222 views

How to avoid redundant code in designing inheritance in C++

Say I have a Base class called Car and it has 3 derived classes say Ford, Honda and Audi. The issue is, all three derived classes have exactly same code but minor difference in calling member ...
17
votes
6answers
6k views

Dependency injection ; good practices to reduce boilerplate code

I have a simple question, and I'm not even sure it has an answer but let's try. I'm coding in C++, and using dependancy injection to avoid global state. This works quite well, and I don't run in ...
9
votes
4answers
1k views

What is use of universal character names in identifiers in C++

The C++ standard (I noticed it in the new one, but it did already exist in C++03) specifies universal character names, written as \uNNNN and \UNNNNNNNN and representing the characters with unicode ...
0
votes
1answer
189 views

Polymorphic engines in C and/or C++ [closed]

I stumbled across polymorphic engines and I don't know anything about them. However, I am curious about how they are written. Every example that I've looked up writes them in assembly, my assembly is ...
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votes
2answers
112 views

Why friend in C++ should be in the header file? [closed]

Friend function/class, FriendOfX for some arbitrary class X is an implementation detail of class X. Why in C++ we have to declare them in the header file? Are there any compelling reasons to make this ...
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votes
3answers
117 views

What's the list of how to precisely talk about problems in C++ code within the spec? [closed]

The C++ specification leaves a lot of leeway such that when you write bad code, compiler authors are not responsible for defining a specific mode of failure. We know of course that is Undefined ...
-3
votes
1answer
117 views

Is this a good use of a base class? [closed]

I am developing some HW drivers, which access registers. I have a few classes, for example. ClassRegisterBlock1, ClassRegisterBlock2. In each of these classes, they define the bits to manipulate, ...
3
votes
5answers
1k views

Boundary conditions for testing

Ok so in a programming test I was given the following question. Question 1 (1 mark) Spot the potential bug in this section of code: void Class::Update( float dt ) { totalTime += dt; ...
2
votes
1answer
205 views

Any OOP design pattern that is somewhat representative of all of the SOLID OOP design principles at play?

I'm trying to teach an object oriented design principles course (on SOLID) at a training institute. I also want to teach the students a few OOP design patterns such as factory, singleton and one ...
4
votes
3answers
4k views

Is it important to obfuscate C++ application code?

In the Java world, it seems to sometimes be a problem, but, what about C++? Are there different solutions? I was thinking about the fact that someone can replace the C++ library of a specific OS ...
1
vote
7answers
684 views

Where is the 'this' variable stored?

Let's take this simple c++ program as an example: #include <vector> class A { void fun() { a = this + 1; } A* a; }; main() { std::vector<A> vec; vec.resize(100); } Forgetting ...
0
votes
2answers
197 views

Mobile App Development-Architecture/Platform: Main performance concern: device/UI responsiveness [closed]

I am currently investigating different alternatives for building a mobile instant messaging application for iOS and Android, using an XMPP server (probably ejabberd) as the back-end. Main requirements ...
-2
votes
1answer
100 views

OOP and Data Structures in C++? [closed]

Is it a must to study Object Oriented Programming before going into Data Structures in the C++ language or can I begin with lists, stacks ,queues,sorting ......etc and does Object Oriented Programming ...
3
votes
2answers
174 views

Are there alternatives to using an optional type in a multithreaded environment?

I'm making an MPMC queue in C++, and I would like to find out what the best interface for a try_dequeue method would be (I'm not concerned about its implementation). I'd like to provide a method which ...
1
vote
3answers
648 views

Is this a good design in C++?

Is it a good idea to replace getters and setters with a single function returning a reference? For example, instead of this, class Person { std::string name; public: std::string GetName() { ...
1
vote
2answers
352 views

2D linked list vs. multidimensional array/vector

I hope that programmers is the correct stack exchange for this, as it is quite a concept based question. I'm working on a data structure in C++ that is a represents data in 3D space. The x-y plane is ...
1
vote
1answer
121 views

Multithreaded Pre/Post Functions

I'm programming an application for an embedded device. We are using an RTOS that supports multi threading. The device is supposed to mimic an older project that was programmed in plain C (without ...
3
votes
2answers
161 views

On concatenating adjacent string literals

C and C++ compiles adjacent string literals as a single string literal. For example this: "Some text..." "and more text" is equivalent to: "Some text...and more text" In other languages like C# ...
2
votes
1answer
76 views

class hierarchy with structurally different subclasses

I want to implement a protocol layer which sits on top of the TCP/IP stack. There is a limited set of PDUs that can be sent and for each PDU there is a class which represents it in a structured form. ...
1
vote
1answer
127 views

How should a GUI application written in WinAPI be structured and organized? [closed]

I've done an extensive amount of GUI programming in Winforms and WPF using C#, and a tiny bit in C++ using MFC. I'm building a personal project using WinAPI mainly to gain a deeper knowledge in ...
0
votes
2answers
79 views

C++ Data Server and J2ME client communication [closed]

I am working on a robot that has some AI built in. However, the mandated robot controller does not have the power to do the work onboard. This means that I need to use a co-processor. I am writing ...