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

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-1
votes
2answers
96 views

What is a simple explanation for the reinterpret_cast expression? [closed]

I see that it is a compiler directive which instructs the compiler, but what does that mean?
1
vote
3answers
353 views

Should I pass array or pointer?

I am writing a C++ library (but prefer C style interface functions) and one of the function returns array of floats. I am not sure if I should pass pointer or fixed array to get this data? // in the ...
0
votes
2answers
125 views

Characterization in Testing: Unit test or Functional test [duplicate]

So I'm trying to push for more automated testing in my company, which focus a lot on prototype and proof of concept systems. We currently use Google Test for unit testing. This tests specific test ...
1
vote
2answers
151 views

Initialization of objects in a system using dependency injection

This is a follow up question to the following post: Injecting dependencies (DI) in c++ applications In a system that uses DI, someone, somewhere should be responsible to create the various objects ...
2
votes
2answers
208 views

Injecting dependencies (DI) in c++ applications

I am playing with dependency injection, but i am not sure I am doing it right. Especially, I am not sure what should be the correct way to build classes with injected dependencies. Say I have a class ...
25
votes
5answers
3k views

Why is it bad to write something in language X as if you're writing a program in language Y in terms of using a shared coding paradigm [closed]

A while ago, I asked a question on SO about something written in C++, but instead of getting an answer to the problem at hand, the comments went all crazy on my coding style, even when I indicated ...
0
votes
2answers
61 views

Mutable cursor in readonly object?

I've been searching for the different uses of the keyword mutable. I've found that it is generally used for caching, lazy computing, mutex, ... But I'm wondering if it is coherent to use it for a ...
0
votes
1answer
234 views

How to use namespaces to separate interface from implementation, in c++?

As far as I can tell, you can make your interface known to others by providing your .h file. Your .cpp is the implementation. Then they can see the function names, the parameter types, the return ...
0
votes
2answers
237 views

What's a DRY alternative to c++ header files? [duplicate]

In c++, is there any other way, besides header files, to use a function defined in file A.cpp, inside file B.cpp that would be considered good programming practice?
0
votes
1answer
166 views

How to reuse c++ code? [closed]

How do I call functions defined outside a source file given you shouldn't use header files? -- EDIT: generic(?) question below So, first, a problem should be broken down into simpler subproblems. ...
1
vote
4answers
284 views

How do you call one program from another?

What I'm wondering is how running programs communicate with each other, and if someone could post some sample code for how to do this, so I can try it out myself, just for educational purposes. For ...
-1
votes
1answer
119 views

Optimal movie schedule

Let's say Mr. A goes to cinema and he gets a movie schedule. There are N movies on the program today (1 < N < 50) and for every movie the time of the start and the time of the end are given in ...
45
votes
10answers
5k views

Is better Show() + Hide() or SetVisible(bool visible)?

What is better and why? (From interface-design point of view) : a) To have two Show() and Hide() functions b) To have one SetVisible(bool visible) function EDIT: For example some object have ...
0
votes
1answer
260 views

Interface questions for using Command Pattern and Dependency Injection together

I have many projects that have essentially the same high level requirement: test all hardware on a device. Each device can have a different communication protocol, requires different test equipment to ...
0
votes
3answers
390 views

Print bottom view of a binary tree

For a binary tree we define horizontal distance as follows: Horizontal distance(hd) of root = 0 If you go left then hd = hd(of its parent)-1, and if you go right then hd = hd(of its ...
3
votes
2answers
274 views

How to find number of points with same minimal distances on matrix

I'm trying to find the number of points in a matrix with the same minimal distances. Start with a MxN matrix, where M and N < 50000. There is given a set of fixed points, with their respective ...
1
vote
2answers
219 views

Is it a good practice to choose the highest warning level in C++ programming? [closed]

I used to select the default warning level in C++ programming. For example, in VS, the default warning level is Level3 (/W3) and No (/WX-) (don't treat warnings as errors). I am wondering is it a ...
4
votes
2answers
163 views

A module which is used by most other modules

I am pursuing object oriented design. So we don't want to use globals but yet sometime we have a module that most other modules use. This means we have to just pass it to all other modules and this ...
1
vote
0answers
128 views

How to extract the active code path from a complex algorithm

I have been puzzled lately by an intruiging idea. I wonder if there is a (known) method to extract the executed source code from a large complex algorithm. I will try to elaborate this question: ...
2
votes
1answer
310 views

When not to move a “C style” code to “C++ or Object Oriented” code?

Context I am (part of team A) developing a piece of functionality which depends on new APIs provided by team B. Old APIs (also provided by Team B) are there and this is how they are being used in our ...
26
votes
7answers
2k views

Disadvantages of scoped-based memory management

I really like scope-based memory management (SBMM), or RAII, as it is more commonly (confusingly?) referred to by the C++ community. As far as I know, except for C++ (and C), there's no other ...
-1
votes
1answer
141 views

Size of objects during Multilevel inheritance [closed]

Below is a pseudo declaration for a multilevel inheritance. Base class ( protected int data) derived1 : virtual public base ( protected int data1 ) derived2 : virtual public base ( protected int ...
3
votes
2answers
234 views

Multiple entrance points in project

My question is related to C++ but it comes from Java actually. When I was programming Java I had multiple classes, which were derived from a base "Test" class. Their purpose was to test things - run ...
1
vote
1answer
144 views

LLVM case: is the success due to the algorithms? [closed]

I'm not sure if this is a subjective question, I hope not but I'm not proficient with LLVM so I'm just wondering: how come it's become so popular and so widespread used in the industry? Were the ...
1
vote
5answers
657 views

How do I deal with global variables in existing legacy code (or, what's better, global hell or pattern hell)?

So... We have this fairly complex project (~10k LOC, but there's duplicated code so it's hard to tell) with hundreds of global variables. The project has more dependencies on other projects, and many ...
10
votes
4answers
1k views

Why do all <algorithm> functions take only ranges, not containers?

There are many useful functions in <algorithm>, but all of them operate on "sequences" - pairs of iterators. E.g., if I have a container and like to run std::accumulate on it, I need to write: ...
11
votes
4answers
714 views

What are the problems of bringing C++-like const into a language?

I am interested in the idea of C++-like const not that particular execution (like casting away const). Take for example C# -- it lacks C++-like const, and the reason for it is the the usual -- people ...
1
vote
2answers
1k views

Is this proper OO design for C++?

I recently took a software processes course and this is my first time attempting OO design on my own. I am trying to follow OO design principles and C++ conventions. I attempted and gave up on MVC for ...
1
vote
4answers
241 views

Learning programming from a book which uses C++98 [closed]

I am learning programming from a book called "Programming Principles and Practice" by Bjarne Stroustrup. It has been highly recommended over here and elsewhere. My only issue is that it uses C++98 and ...
1
vote
1answer
294 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 ...
-1
votes
2answers
666 views

C#/C++ GUI development without drag and drop? [closed]

I'm currently programming Java, I have played around with C++ before, but I have never touched GUI as I feel "cheat-like" when using its drag and drop system. I feel good and enjoy programming my own ...
27
votes
3answers
2k views

Why does the boolean type in C++ support `++` but not `--`?

Why does the operator -- not exist for bool whereas it does for operator ++? I tried in C++, and I do not know if my question apply to another language. I will glad to know also. I know, I can use ...
0
votes
2answers
275 views

Shared source file between two parts of project [closed]

I have the following sort of directory structure: part1 build src part2 build src Now I have a header file that I would like to include in both parts of these projects, it will ...
3
votes
2answers
268 views

Speed difference between VM-based and compiled code [closed]

Not so long ago I was told by a senior academic that, these days, VM-based code could run nearly as fast as compiled code, but my own experience is that compiled code runs several orders of time ...
1
vote
1answer
162 views

Chained ruleset parsing and evaluation code: recommendations?

So I have to write a filtering system, which may apply preprocessed ruleset to data - and trigger some actions defined in the ruleset while continuing its evaluation. <ruleset name="1"> ...
7
votes
4answers
711 views

Apple eating problem

Player A and Player B play a game. On the middle of the table there is a pot full of N apples of different weights. Player A starts first and choose an apple and start eating it. Losing no time player ...
0
votes
2answers
179 views

In C++ what is the commonly accepted method for making a program platform-agnostic? [closed]

The way I usually do it is I make some namespace Platform in Platform.h and every OS call is encapsulated by a static function in this namespace. So the only place in the entire code base that knows ...
5
votes
3answers
674 views

Member functions vs. Non-member functions for math operators

I'm writing a linear algebra library (long story short, it's a school assignment) that involves matrices, vectors, etc. In the process of creating this library, I'm going to be creating functions ...
0
votes
2answers
123 views

Design principles : classifying different types of class [closed]

I'm trying to clarify the design of a C++ application, and would like to define a clear classification among classes to aid clarity. However I'm struggling to find any literature to help me, probably ...
1
vote
3answers
206 views

C++ project organization to reduce unit testing build time

I want to organize tests for a project large enough that build time matters (especially for the CI server). Say I have this code that I would like to test : //foo/greet.cpp #include <stdio.h> ...
0
votes
0answers
62 views

On the process of replacing an internal framework by a public one [duplicate]

I am working on several applications which depends on a framework which was developed by a prior engineer in the company. The framework was mainly developed and maintained in the early 2000s, and ...
1
vote
1answer
486 views

Running a process multiple times at the same time

I have a c++ program with opencv library which takes an image as input and perform pose estimation,color detection,phog. When I run this program from the command line it takes around 4-5sec to ...
0
votes
0answers
30 views

Offload traces into shared memory

There is a task to trace thread execution activity for posthumous analysis with minimum impact on latency/performance. Stack trace might be not enough to understand the reason of crash. Initially I ...
1
vote
1answer
69 views

How to convey lifetime requirements?

Usually I use std::unique_ptr to convey ownership and pass in raw pointers as parameters when no ownership is implied. However, I almost never consider a nullptr to be acceptable as an argument, so it ...
1
vote
3answers
224 views

How to manage focus for a small set of simple widgets

I'm developing a set of simple widgets for a small (128x128) display. For example I'd like to have a main screen with an overlay menu which I can use to toggle visibilty of main screen elements. Each ...
2
votes
2answers
491 views

Doing work in vector's push back

I often use the following syntax: std::vector<foo> vec; vec.push_back( someClass.getFoo(...).modifyAndReturn() ); Considered about exception safety, I quote the standard on vector's push back ...
1
vote
1answer
191 views

Are there advantages to declaring stack variables constant in C++

It's not clear to me what benefits there are of declaring your stack variables as constant in C++, I was hoping somebody might explain the benefits and purpose for this technique. For example: void ...
0
votes
4answers
544 views

How does assembly relate to machine/binary code

How does assembly relate to machine/binary code. For example here is how to print to the screen in mikeOS(a small pure assembly OS), mikeOS it uses NASM to assemble. BITS 16 ORG 32768 ...
4
votes
3answers
649 views

What are my options for using a C++11 library in a C# WPF application? [closed]

I am writing a cross-platform (OS X and Windows) desktop application in C++11. I intend to use the same C++11 core on both platforms, utilizing native frameworks for the UI (Cocoa and Objective-C on ...
-1
votes
1answer
247 views

Live share prices for a side project [closed]

Me and some of my friends would want to start a side project which we will work at our spare time. Here is our criteria 1) A challenging project which will teach us skills which has business value in ...