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Design Patterns provide solutions to the commonly occurring problems in software design. The design patterns were first introduced by GoF(Gang of Four) where they described the common patterns as problems which occur over and over again and solutions to those problems. Design patterns have four ess...

package main import ( "fmt" "time" ) func say(s string) { for i := 0; i < 5; i++ { time.Sleep(100 * time.Millisecond) fmt.Println(s) } } func main() { go say("world") say("hello") } A goroutine ...

To initialize struct, you can do like this : public static void main (string[] args) { Value val = Value (typeof (int)); val.set_int (33); } But Vala brings another way to initialize values : public static void main (string[] args) { Value val = 33; } Your value is initializ...

Use one of GLib.Value get methods (see valadoc documentation) or cast your value with the type of your value : public static void main (string[] args) { Value val = 33; int i = val.get_int(); int j = (int)val; } Note : if your current value doesn't contain desired type, GObject s...

This exemple shows how you can pass several types in function parameters : static void print_value (Value val) { print ("value-type : %s\n", val.type().name()); print ("value-content : %s\n\n", val.strdup_contents()); } public static void main (string[] args) { ...

In previous example, Value.strdup_contents prints GLib.DateTime as pointer address. You can register functions that will transform value to desired type. First, create a function that will have this signature : static void datetime_to_string (Value src_value, ref Value dest_value) { DateTime ...

The GLib.Task provide low-level API for performing asynchronous operations. var task = new GLib.Task (null, null, (obj, result) => { try { var ret = result.propagate_boolean (); } catch (Error err) { // handler err... } }); Later in a thread or a callback: t...

It is possible to add the attribute hreflang to the elements <a> and <area> that create hyperlinks. Such it specifies the language of the linked resource. The language defined must be a valid BCP 47[1] language tag. <p> <a href="example.org" hreflang="en&quo...

it caused by your batch size too small, which lead to a lot of ROS Containers created and reach the limitation(1024 default). you should do defragment using TupleMover task(mergeout) before the error raised. To do troubleshooting: ROS Containers viewed from the projections. select * from STOR...

it often happened some rows with format issue, data type issue rejected by copy command while try load it by copy command. the query return succeed but some of data rejected. To do troubleshooting save Rejected Data and Exceptions COPY large_tbl FROM :file1 ON site01, :file2 O...

It's necessary to declare the type; here t_my_list; a collection is a TABLE OF something CREATE OR REPLACE TYPE t_my_list AS TABLE OF VARCHAR2(100); Here's the function. Notice the () used as a kind of constructor, and the COUNT and EXTEND keywords that help you create and grow your collection; ...

Before deploying the angular project in server we need to build angular project for production. We also need to change the routing path in index.html file from <base href=”/”> to <base href=”./”> if it is not done then your project wouldn’t get loaded properly there will be some routing ...

ng build –prod Above given command with extra option like –prod would generate the production build project bundle. Once the above command gets executed in the root directory of your project would appear a directory called dist. In which all the production build bundle of your project appears in ...

Once the dist directory is ready with your production built bundles. Just open the dist directory and open the command prompt type the following command to create the war file to deploy your project on apache tomcat server. jar cvf dist.war . Once the above jar commands gets executed. It wou...

Cut/Copy the dist.war file from dist directory and place it in apache tomcat webapp directory. Go to apache tomcat bin folder and double click on startup.bat file. Now tomcat server will execute dist.war file and startup the tomcat catalina server. Once the tomcat catalina server gets started o...

Install virtualenv via pip / (apt-get): pip install virtualenv OR apt-get install python-virtualenv Note: In case you are getting permission issues, use sudo.

If you look at the bin directory in your virtualenv, you’ll see easy_install which has been modified to put eggs and packages in the virtualenv’s site-packages directory. To install an app in your virtual environment: $ source test_project/bin/activate $ pip install flask At this time, you do...

lsvirtualenv : List all of the environments. cdvirtualenv : Navigate into the directory of the currently activated virtual environment, so you can browse its site-packages, for example. cdsitepackages : Like the above, but directly into site-packages directory. lssitepackages : Shows contents of ...

The window.postMessage() method together with its relative event handler window.onmessage can be safely used to enable cross-origin communication. The postMessage() method of the target window can be called to send a message to another window, which will be able to intercept it with its onmessage e...

&& has precedence over ||, this means that parentheses are placed to evaluate what would be evaluated together. c++ uses short-circuit evaluation in && and || to not do unnecessary executions. If the left hand side of || returns true the right hand side does not need to be evaluate...