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In object-oriented design, the chain-of-responsibility pattern is a design pattern consisting of a source of command objects and a series of processing objects. Each processing object contains logic that defines the types of command objects that it can handle; the rest are passed to the next proce...

Create a sample table on a sample database CREATE TABLE [dbo].[Table_1]( [Id] [int] IDENTITY(1,1) NOT NULL, [title] [varchar](50) NULL, CONSTRAINT [PK_Table_1] PRIMARY KEY CLUSTERED ( [Id] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_...

Expressions in Java are the primary construct for doing calculations. Here are some examples: 1 // A simple literal is an expression 1 + 2 // A simple expression that adds two numbers (i + j) / k // An expression with multiple operations (flag) ? c : d // An...

Some times you see a signal is emitted in sender thread but connected slot doesn't called (in other words it doesn't receive signal), you have asked about it and finaly got that the connection type Qt::DirectConnection would fix it, so the problem found and everything is ok. But generaly this is ba...

set oDic = CreateObject("Scripting.Dictionary") oDic.add "USA", "United States of America" oDic.add "UK", "United Kingdom" oDic.add "CAN", "Canada" For Each obj in oDic.Items Msgbox obj Next Set oDic = Nothing *Out...

set oDic = CreateObject("Scripting.Dictionary") oDic.add "USA", "United States of America" oDic.add "UK", "United Kingdom" oDic.add "CAN", "Canada" For Each obj in oDic.keys Msgbox "Key: " & obj & &quo...

set oDic = CreateObject("Scripting.Dictionary") oDic.add "USA", "United States of America" oDic.add "UK", "United Kingdom" oDic.add "CAN", "Canada" ' Delete only if Key exists If oDic.Exists("UK") Then oDic.R...

UseExceptionHandler can be used to handle exceptions globally. You can get all the details of exception object like Stack Trace, Inner exception and others. And then you can show them on screen. You can easily implement like this. app.UseExceptionHandler( options => { options.Run( as...

How do you detect them? If the same variable/resource/memory location is accessible by multiple threads and at least of the thread is changing the value of variable/resource/memory location, then Race Condition can occurred. Because if a thread is changing the value of variable/resource/memory ...

Higher-order functions take other functions as arguments and/or return them as results. They form the building blocks of functional programming. Most functional languages have some form of filter function, for example. This is a higher-order function, taking a list and a predicate (function that ret...

Overview Openssl consists of 2 libraries: libcrypto and libssl. Before openssl API can be used in an application, mandatory initialization procedures are expected to be performed. Once application is done with openssl related work, it is expected to cleanup allocated resources. Code below does com...

iOS 10 Now Requires User Permission to Access Media Library, Photos, Camera and other Hardware like these. The solution for this is to add their keys into info.plist with description for user that how we are using their data , iOS already required permissions to access microphone, camera, and m...

#include <gtk/gtk.h>//jjk.c static void destroy(GtkWidget *widget, gpointer data) { gtk_main_quit(); } int main(int argc, char *argv[]) { gtk_init(&argc, &argv); GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL); gtk_window_set_title(GTK_WINDOW(window), "Window&quot...

A typical use case for RxJS is creating HTTP requests and caching their results for some period of time. Also, we always want to run only one request at a time and share its response. For example the following code caches 1 item for max. 1000ms: var updateRequest = Observable.defer(() => makeMo...

A very easy way to connect to an ORACLE database is by using oracledb module. This module handles the connection between your Node.js app and Oracle server. You can install it like any other module: npm install oracledb Now you have to create an ORACLE connection, which you can later query. co...

Use may now use the connExecute-Function for executing a query. You have the option to get the query result as an object or array. The result ist printed to console.log. function connExecute(err, connection) { if (err) { console.error(err.message); return; } sql = ...

Location is a service that applications can use to interact with a browser's URL. Depending on which LocationStrategy is used, Location will either persist to the URL's path or the URL's hash segment. Location is responsible for normalizing the URL against the application's base href. import {Comp...

Given data Const c a = Const c we have data Free (Const c) a = Pure a | Free (Const c) which is isomorphic to data Either c a = Right a | Left c

Given data Const c a = Const c we have data Cofree (Const c) a = a :< Const c which is isomorphic to data Writer c a = Writer c a

Given data Maybe a = Just a | Nothing we have data Cofree Maybe a = a :< Just (Cofree Maybe a) | a :< Nothing which is isomorphic to data NonEmpty a = NECons a (NonEmpty a) | NESingle a