The tag has no wiki summary.

learn more… | top users | synonyms (1)

11
votes
2answers
2k views

Is this a good pattern: replacing a long function with a series of lambdas?

I recently run into the following situation. class A{ public: void calculate(T inputs); } Firstly, A represents an object in the physical world, which is a strong argument for not splitting the ...
3
votes
2answers
134 views

Will destructing a large list overflow my stack?

Consider the following singly linked list implementation: struct node { std::unique_ptr<node> next; ComplicatedDestructorClass data; } Now, suppose I stop using some ...
-4
votes
0answers
41 views

“= default” about constructor in c++ [on hold]

struct Sale{ Sale () = default;//I got nothing about those cod Sale(std::istream &input); Sale(const std::string &s):book(s) {} //and so on...... } What did the second code mean? Is that ...
-4
votes
0answers
29 views

I need Help making a flowchart [on hold]

I have never made a flowchart before and have no experiance of it. I know what standard symbols and their meaning but I need some examples. If anyone can convert the following code in flowchart form ...
2
votes
1answer
44 views

Should a lockfree queue use a condition variable?

Suppose I have a lockfree queue in a multithreaded setting. I already provide a try_dequeue() method which allows for an optional failure (communicated via the return type) if the queue is empty. ...
1
vote
0answers
52 views

How can set different function signature to the same function pointer? [migrated]

How can I set a function pointer depending on some condition to functions with different signature? Example: short int A() { return 0; } long int B() { return 0; } void main() { ...
2
votes
1answer
75 views

How to make max-heap stable with counter and account for counter overflow?

Generally I need size-efficient data structure similar to std::priority_queue but stable (preserving order of insertion). By adding just 4 bytes to the object I could have 1 byte serving as priority ...
3
votes
2answers
168 views

How to deal with historic exception specifications in maintained C++ code

Today, I discovered a few exception specifications in legacy code I've to maintain, when Cppcheck 1.68 ([Inconclusive] but correctly) pointed out that the specified exceptions are not handled in ...
7
votes
1answer
177 views

Message Queue for RTOS for microcontrollers

I'm currently writing an RTOS for microcontrollers. The whole thing is written in C++11 - if anyone is interested, and the link to the repository is at the bottom. Currently I'm writing a class that ...
2
votes
5answers
486 views

Why lambda/closures expressions came so late to C++?

I was reading a really great Bjarne Stroustrup's article where he exposes some C++ myths. I look at code that focus my attention, because I wouldn't know that C++ supports this kind of expressions. ...
1
vote
0answers
95 views

Too many parameters to data processing class constructor

I have a conceptually simple application: data comes in as small encrypted packets, they decrypted and validated, some are stored in the database, some rules are applied, and a reply might be ...
4
votes
1answer
422 views

Move semantics in C++ - Move-return of local variables

My understanding is that in C++11, when you return a local variable from a function by value, the compiler is allowed to treat that variable as an r-value reference and 'move' it out of the function ...
12
votes
2answers
584 views

Who is to blame for this range based for over a reference to temporary?

The following code looks rather harmless on first sight. A user uses the function bar() to interact with some library functionality. (This may have even worked for a long time since bar() returned a ...
77
votes
13answers
10k views

Does auto make C++ code harder to understand?

I saw a conference by Herb Sutter where he encourages every C++ programmer to use auto. I had to read C# code some time ago where var was extensively used and the code was very hard to ...
3
votes
3answers
2k views

How to setup the c++ rule of three in a virtual base class

I am trying to create a pure virtual base class (or simulated pure virtual) my goal: User can't create instances of BaseClass. Derived classes have to implement default constructor, copy ...
3
votes
6answers
768 views

Unit test private method in c++ using a friend class

I know that this is a debated practice, but let's suppose that this is the best option for me. I am wondering about what is the actual technique to do this. The approach that I see is this: 1) Make a ...
-2
votes
2answers
101 views

Comparing doubles [duplicate]

I need to compare to double variables like this if (distance <= radius) both distance and radius are doubles and I remember in class how to use epsilon comparisons for checking equality but how ...
0
votes
1answer
40 views

confusion regarding handling of new smart pointers on stack frames?

Let me try to elaborate it. Stack Frame: When we execute any function it create stack where all local variables and instructions reside. And Smart Pointer: smart pointer like std::unique_ptr allows ...
1
vote
3answers
474 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
317 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 ...
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 ...
-3
votes
2answers
174 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 ...
1
vote
2answers
182 views

Is it an anti-pattern to use void* and enums to enable type-checking?

Say in a game engine, you have Objects that composited of different components. One of these is a RenderComponent which can be either a Mesh, a Sprite or a Light. Now, all these are vastly different ...
0
votes
1answer
93 views

In C++11 can Auto be used to get around mis-casting of void * parameters in functions?

If I have a generic function that takes a void* as a parameter, can Auto in C++11 help stop any bad casting of that parameter? For instance, we may have an event system that sends events and a ...
17
votes
10answers
19k views

Why would I learn C++11, having known C and C++? [closed]

I am a programmer in C and C++, although I don't stick to either language and write a mixture of the two. Sometimes having code in classes, possibly with operator overloading, or templates and the oh ...
0
votes
0answers
26 views

Using rvalue references to signal function behaviour [duplicate]

I have been using functions accepting rvalue ref signatures to make explicit at call site that the object passed in effectively ceases to exist. This ensures that I don't mistake this function for one ...
0
votes
4answers
179 views

Cross Platform Compilation of C++ .exe

I have been asked to re-write an old C/C++ project in C++11. The old project is multi-platform, however, in order to deploy the system on other architectures the current process is to log into a ...
1
vote
2answers
132 views

The destination of cout messages in a GUI program

I've been building some classes and functions in a static library which has the familiar printing of text messages to stdout: cout << "Hello World!" << endl; I've been developing this ...
2
votes
1answer
74 views

How to define different names for the same type and have the compiler check them? [duplicate]

I would like to define several names for the same type and have the compiler distinguish between them. My motivation is that different int variables could represent very different units, and I would ...
2
votes
1answer
221 views

High-level description of how experimental C++ features are developed?

Herb Sutter in a video answers a question about the concepts proposal considered for C++11 and from his remarks it sounds like multiple groups offered prototype implementations but all of them left ...
20
votes
2answers
1k views

C++ strongly typed typedef

I've been trying to think of a way of declaring strongly typed typedefs, to catch a certain class of bugs in the compilation stage. It's often the case that I'll typedef an int into several types of ...
3
votes
1answer
352 views

How to maintain encapsulation with composition in C++?

I am designing a class Master that is composed from multiple other classes, A, Base, C and D. These four classes have absolutely no use outside of Master and are meant to split up its functionality ...
5
votes
2answers
1k views

Should I feel “uncomfortable” using auto in C++? [duplicate]

C++11 features the new auto type declaration, allowing you to work with an object without ever knowing its actual type. I use only strongly typed languages - C++, Delphi (Object Pascal), Go, etc and ...
1
vote
1answer
161 views

heading in right direction? C++ and class templates

I'm working on some inherited code in C++ and am trying to use 2 classes with templates as I need 2-types of each class to operate on floating point or integer data (double v uint64_t to be exact). ...
0
votes
3answers
384 views

Why std::allocators are not that popular? [closed]

With the latest trends about C and C++ applications, and with latest I mean the latest years, I was expecting to see std::allocators to be used way more frequently than what it really is. Modern ...
3
votes
2answers
387 views

Intersection of geometric entities

I was trying to design a small C++ geometric API for learning purposes, but came across a problem when dealing with intersections of geometric entities. For example, the intersection of a line and a ...
11
votes
5answers
16k views

Should I use the new C++11 'auto' feature, especially in loops?

What are the pros/cons to using the auto keyword, especially in for loops? for(std::vector<T>::iterator it = x.begin(); it != x.end(); i++) { it->something(); } ...
2
votes
3answers
345 views

Why are pointers to literals not possible?

Reference to a literal is possible only if the reference is declared as constant. But why is a pointer to a const object not possible in case of literals? i.e. int const& ref = 5;// But why ...
22
votes
4answers
10k views

Using scoped enums for bit flags in C++

An enum X : int (C#) or enum class X : int (C++11) is a type that has a hidden inner field of int that can hold any value. In addition, a number of predefined constants of X are defined on the enum. ...
28
votes
6answers
6k views

What does the latest “C++ Renaissance” mean? [closed]

There's recently some voice about C++ renaissance, among which the most noteworthy one is from Herb Sutter, Chairman of the C++ Standard Committee. You can search for "C++ renaissance" on Google and ...
4
votes
3answers
969 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
vote
3answers
275 views

C API in C++ with RAII, two alternatives to implement error handling (Exceptions)

I have an API written in C, which produces a result by returning a pointer to allocated memory. For using it with C++ (C++11) I've wrapped the function calls in objects, which keep the result in a ...
26
votes
10answers
7k views

I am a beginner. Can I directly start learning C++11? or I have to learn old C++? [closed]

I'm a beginner and have only little knowledge in programming. Would it be good if I directly learn C++ from books which cover new C++11 or should I study through the old best C++ books? Should I ...
10
votes
3answers
2k views

Style guide for C++

Right now I am using Google C++ Style Guide in my C++ code and I was pretty happy with it. Recently I was told that this guide is very bad: it is used internally by Google (I knew that), is outdated, ...
1
vote
1answer
97 views

argument grouping with parenthesis are valid in C++?

On python I can group arguments into a tuple, something like def func((a, b, c, d), x): print a, b, c, d, x I was wondering if it is possible to group arguments in the same way on C++, ...
21
votes
8answers
3k views

Deprecation considered harmful? [closed]

I've just been compiling some of my own code with the -std=c++0x flag in GCC, as I want to vaguely keep up with what all the young folks are doing (provided they stay of my lawn), and I ended up with ...
1
vote
2answers
349 views

Documenting the effect of std::move

As my team move towards embracing the new features in C++11 I'm struggling with how to make the side-effects of std::move self-documenting in the code. The issue is that an object that has been moved ...
0
votes
0answers
85 views

why c++11 define closure as a process of capturing variables

when using closure in other languages, it just feels nature, variables from outer scope are captured automatically , without the need of declaring such captures. in c++11, good to see we have ...
2
votes
3answers
315 views

Can compilers check whether certain axioms hold for a user defined type?

Suppose the following type is defined (C++ syntax, can be conceptually applied to any statically typed language.) class T { int val; friend bool operator<(const T& lhs, const T& rhs) ...
9
votes
3answers
2k views

Achieving forward compatibility with C++11

I work on a large software application that must run on several platforms. Some of these platforms support some features of C++11 (e.g. MSVS 2010) and some don't support any (e.g. GCC 4.3.x). I ...