Questions tagged [callback]
Callback is facility to save a piece of code so that it may be invoked later in the current environment (Typically in response to an event)
171 questions
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Is this a sane (as in lacking UB) implementation of a ref-counted subscription cleanup?
AutoCancel is a class which wraps a Cancel (aka void()) function. The purpose of wrapping ...
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Member (virtual or not) function to C callback by generating static version at compile time
I've started to write a header-only implementation of callback for member functions :
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C++ Structural Requests System with Payload Management
First things first, I'd thank Mr. G. Sliepen and Mr. Davislor regarding their help in the previous questions (C++ System data transfer design) (C++ System data transfer design - Following 1), given ...
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c++ multithreaded message broadcaster with link lifetime management v3
note: This is v3 of code that was previously reviewed.
I have written a class that handles listeners registering callbacks to receive messages. Link lifetime is managed (or is it? See below). Code is ...
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An NVIDIA Jetson Nano GPIO Wheel Encoder Message Publisher using ROS2
Although this code uses ros2 my concern is about C++ code quality, because I still struggle when it comes to making good design ...
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Delphi - did I understand callbacks correctly?
I am trying to learn callbacks in Delphi (7). Could not find a complete simple tutorial, so I puzzled together a few bits here and there. This is my first attempt, of course trivial.
My form contains ...
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Wait for a callback and then using the result
I'm using Frida to run a script on a process, and I want to wait for it to send the result back to me, as a callback.
My current code looks like this:
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TFunction: std::function replacement for event system
I've been trying to implement delegate for my event system. I thought that maybe std::function can do the trick for me, but it turned out to be not comparable, so what i have end up doing is this - ...
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Event callbacks library
This is a small library I wrote to make event callbacks with variadic templates work like C#'s event system (placeholder template by "dyp" at http://stackoverflow.com/a/21664270).
Just like ...
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c++ multithreaded message broadcaster with link lifetime management v2
note: This is v2 of code that was previously reviewed.
I have written a class that handles listeners registering callbacks to receive messages. Link lifetime is managed (or is it?). Code is ...
1
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1
answer
111
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c++ multithreaded message broadcaster with link lifetime management
note: A version of this code without link lifetime management was previously reviewed. Adding lifetime management actually made the code simpler, and the class simpler to use.
I have written a class ...
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Generic Event class
C++ Event class
From the desire of having a callback function which includes a void* userdata argument, I've made this generic event class.
It is tested and working, but some desired features are ...
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C++ Observer Pattern with std::function
I am/we are using the observer pattern for many things in our application. I think it's time to create a reusable base class for these situations. Most implementations I could find only do something ...
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Simplify 2D point angle comparator
I have a comparison function for comparing two points in 2 (or more) dimensions based on the angle of each point in standard polar coordinates. In other words, a point ...
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C++ Generic Callback class with removable listeners by unique id
I'm quite new to the STL.
Does this make sense? Is there a better way of removing the listeners instead of using shared_ptr while keeping the code short and simple? Is there something in the STL to ...
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c++ multithreaded message broadcaster using callbacks
note: This is an updated design after a previous review round.
I have written a class that handles listeners registering callbacks to receive messages. Registered callbacks can be replaced or removed. ...
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C++ callback multithreaded, can unregister itself
update: a new version of this code is posted here
With this post, i would like to 1) ask for feedback on below code as it stands:
do i apply all best practices for c++20?
is it safe?
is my way to ...
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Cyclic generator with access to current local state and executes callback after each cycle
I'm working on a Python class that is a cyclic generator, like itertools.cycle, but it offers access to its current state and executes a callback after the ...
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Error Code Stack Trace and Propagation Library in C
I've been programming in Go and I enjoy how easy it is to create descriptive errors and propagate them up the call stack. I wanted that sort of ease and consistency in C so I created a small error ...
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Supplying parameterless callback to function expecting void * param
I have to register different callback functions to a scheduler. The callback signature defines a void * parameter. Some callbacks don't use a parameter. This works, ...
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Login system using callbacks in android
I wrote a login system for an app I am developing, but I'm not really happy with the code I have at the moment. I feel like there is a better way at tackling a problem like this. In particular I'm not ...
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Callback C++ Class method from C
I am trying to callback C++ class methods from C. Now I have got something working, but am not sure if this is the best solution.
I am looking for feedback, as to if there is something wrong with this ...
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Registering a user and login
I have these following controller functions for registering a user and login, in my app, and I want to make it more clean and maintainable.
Probably by using ...
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407
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Message Broadcaster
I've written a basic event messenger broadcasting service. This is meant to allow for broadcasting events between loosely coupled areas of code where you may not have or care about a direct reference ...
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callback function with no dynamic memory allocation
I tried to make a callback type for embedded, I know std::function and lambda but I know that there is some dynamic memory allocation that I want to avoid, I came ...
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It's Teetime; adding tee like functionality to Popen
I recently needed to run some command line applications from Python. Whilst this is fairly simple with subprocess.Popen. I wanted to be able to properly pipe the ...
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Bitmask, How to abstract those callbacks in this implementation
I've made an POC about a bitmask implementation in order to replace a huge if/else statement.
Those statements are about strings and I have almost 15 /20 string to test. Depends on values the if/else ...
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Simple replacement for Redux in ES6
The idea about this code is that it's a full replacement of Redux — in 22 lines of code.
...
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Implementation of a Thread Pool in C++
I wanted to implement a thread pool to test my knowledge of various modern C++ features. The end result could be better, but I need a review as I'm not sure about delicate things especially regarding ...
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Customizable unidirectional questionaire in javascript
I wrote the below answer for the following question on SO a couple of days ago, and I was curious if the usage of the generator function is an acceptable one.
I choose the generator function, because ...
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Callback usage with custom Stack Exchange Flair
Today I decided to continue refining my JavaScript skills and utilized the Stack Exchange API (v2.2) to write a "user flair" replica.
In case you don't know what the flair that SE provides is:
The ...
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Ajax function with a callback
I have Ajax function with a callback which fetches all the Patient data however I have some perfomance issues and trying to figure out what it might be, does anyone have idea? That's my Code
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std::function alternative with no dependencies
An alternative to std::function for when compile time is more important than runtime performance. Doesn't pull in any headers.
(...
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Wrap a callback method in an awaitable method
I'm using a .NET library which uses a pre-async/await type of asynchronicity. That is, it provides asynchronous (non-awaitable) method with a callback parameter.
I'm trying to write awaitable ...
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Chaining ConstrainableSet<T> [closed]
Based on feedback on my previous question, I made many small adjustments to the code, added more APIs and tried to follow through with delivering on the excellent advice I have received in regards to ...
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Constraining a property setter fluently
The below code is aimed at providing you the most amount of control and flexibility with control which value gets set to a property.
I Introduce to you, the ...
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C# asynchronous notification vector
The purpose of this class is to efficiently notify another thread when data is available with minimal blocking to access/pass the data. The data reader/producer thread processes data in bulk which ...
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UI Event Flow class
Purpose:
I wanted a way to improve event clarity and event code organization. I
observed that every single event flow went through the following
steps:
Trigger -> UI Change -> (Async) ...
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Function to call a list of callables with retry
This script is designed to be run via windows task scheduler once per day.
All callables passed to this function should only return a bool. The callables are called until either the maximum number of ...
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Updating one model field based on the associated model's field
I'm wondering if there is any way we can optimize the following code.
Scenario is Library's active field should be ...
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Simple Publisher Subscriber in Java
I am new to Java and had some difficulty creating this simple Publisher Subscriber class. It finally seems to be working and I wanted to check if I have been following best practices and see if there ...
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C++ wrapper for GLFW window object
I'm creating a window class in C++ to provide a bit of abstraction for a GLFW window.
window.h
...
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pass argument to jQuery .on() event handler callback [closed]
In my web application, a user will click a button which will call a function that triggers an AJAX call. That function accepts a single argument. I would like to be able to put that function in ...
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Event emitter npm module
I was asked to complete the task described below:
Event Emitters are objects that serve as the core building block in event-driven architectures. They simplify the process of handling asynchronous
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jQuery handler to update map UI based on AJAX response
I am working on a university project that consists of creating a map application with openlayers as well as the necessary User-Interface. I am using jQuery, native JavaScript, PHP and of course HTML/...
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Simple event dispatcher
Here is my very first event dispatcher. I would like to get both, style and code review, as well as some ideas to improve this implementation (new features etc.)
I tried to write code in C++17 style ...
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Class that provides callback execution at a specified rate
Here is a class I wrote to provide a user a way to have a callback function executed at some defined frequency:
Task.hpp
...
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Extracting data from vue-chartjs into an array of datasets
I have a function which returns an array of datasets for a chart written with vue-chartjs. The getter getChartData returns an array with three objects with nested ...
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Controller to execute AJAX requests for a client
I have been developing this structure or pattern (I don't really know how to call it). It's my first time doing something like this, and I'm a bit worried about the future, if it becomes unmanageable.
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