Tutorial by Examples: d

Note that many datatypes don't need to be quoted, since they evaluate to themselves. QUOTE is especially useful for symbols and lists, to prevent evaluation as Lisp forms. Example for other datatypes not needed to be quoted to prevent evaluation: strings, numbers, characters, CLOS objects, ... Her...

class MyHello { def sayHello() { "Hello, world" } } def cl = { sayHello() } cl() // groovy.lang.MissingMethodException cl.delegate = new MyHello() cl(); // "Hello, world" Used extensively by Groovy DSLs.

DateTime now = new DateTime.now(); DateTime berlinWallFell = new DateTime(1989, 11, 9); DateTime moonLanding = DateTime.parse("1969-07-20 20:18:00"); // 8:18pm You can find more in depth information here.

Sending events is as easy as creating the Event object and then posting it. EventBus.getDefault().post(new ArbitaryEvent(ArbitaryEvent.TYPE_1));

Declared variable without a value will have the value undefined var a; console.log(a); // logs: undefined Trying to retrieve the value of undeclared variables results in a ReferenceError. However, both the type of undeclared and unitialized variables is "undefined": var a; console...

variables var = 50 -- a global variable print(var) --> 50 do local var = 100 -- a local variable print(var) --> 100 end print(var) --> 50 -- The global var (50) still exists -- The local var (100) has gone out of scope and can't be accessed any longer. types num = 20 -- a ...

A patch is a file that show the differences between two revisions or between your local repository and the last revision your repository is pointing. To share or save a patch of your local uncommitted changes either for peer review or to apply later, do: svn diff > new-feature.patch To get a...

C99 These functions returns the floating-point remainder of the division of x/y. The returned value has the same sign as x. Single Precision: #include <math.h> /* for fmodf() */ #include <stdio.h> /* for printf() */ int main(void) { float x = 10.0; float y = 5.1; ...

Creating a database in a particular location. If we dont specify any location for database its created in warehouse directory. CREATE DATABASE IF NOT EXISTS db_name COMMENT 'TEST DATABASE' LOCATION /PATH/HDFS/DATABASE/;

1. Passing integer data: SenderActivity Intent myIntent = new Intent(SenderActivity.this, ReceiverActivity.class); myIntent.putExtra("intVariableName", intValue); startActivity(myIntent); ReceiverActivity Intent mIntent = getIntent(); int intValue = mIntent.getIntExtra("intVa...

To change UI content in runtime, you can use Binding. When binded property is changed from the code, it will be displayed to the UI. <TextBlock Text="{Binding Title}"/> To notify UI about changes, property must raise PropertyChanged event from INotifyPropertyChanged interface or ...

In addition to the concept of column units, Bootstrap has different breakpoints or grid sizes known as tiers. The Bootstrap 3 grid has four (4) tiers to accomodate different screen (or viewport) widths. The Bootstrap 3 tiers are xs, sm, md, and lg. Bootstrap’s grid columns are identified by differen...

If you're doing multiple long calculations, you can run them at the same time on different threads on your computer. To do this, we make a new Thread and have it point to a different method. using System.Threading; class MainClass { static void Main() { var thread = new Thread(Seco...

using System.Threading; class MainClass { static void Main() { var thread = new Thread(Secondary); thread.Start("SecondThread"); } static void Secondary(object threadName) { System.Console.WriteLine("Hello World from thread: " + thread...

Environment.ProcessorCount Gets the number of logical processors on the current machine. The CLR will then schedule each thread to a logical processor, this theoretically could mean each thread on a different logical processor, all threads on a single logical processor or some other combination...

Sometimes, you want your threads to simultaneously share data. When this happens it is important to be aware of the code and lock any parts that could go wrong. A simple example of two threads counting is shown below. Here is some dangerous (incorrect) code: using System.Threading; class MainCl...

Using a doc comment instead of a regular comment enables dartdoc to find it and generate documentation for it. /// The number of characters in this chunk when unsplit. int get length => ... You are allowed to use most markdown formatting in your doc comments and dartdoc will process it accor...

Processing tabular data with awk is very easy, provided that the input is correctly formatted. Most software producing tabular data use specific features of this family of formats, and awk programs processing tabular data are often specific to a data produced by a specific software. If a more gener...

Given a file using ; as a column delimiter. Permuting the first and the second column is accomplished by awk -F';' -v 'OFS=;' '{ swap = $2; $2 = $1; $1 = swap; print }'

Given a file using ; as a column delimiter. We compute the mean of the values in the second column with the following program, the provided input is the list of grades of a student group: awk -F';' '{ sum += $2 } END { print(sum / NR) }' <<EOF Alice;2 Victor;1 Barbara;1 Casper;4 Deborah;...