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To create a build target producing an executable, one should use the add_executable command: add_executable(my_exe main.cpp utilities.cpp) This creates a build target, e.g. make my_exe for GNU make, with the appropriate invocations of the configured compiler to pr...

To create an build target that creates an library, use the add_library command: add_library(my_lib lib.cpp) The CMake variable BUILD_SHARED_LIBS controls whenever to build an static (OFF) or an shared (ON) library, using for example cmake .. -DBUILD_SHARED_LIBS=ON. However, you can explicitly se...

The =~ operator attempts to match a regular expression (set apart by /) to a string: my $str = "hello world"; print "Hi, yourself!\n" if $str =~ /^hello/; /^hello/ is the actual regular expression. The ^ is a special character that tells the regular expression to start with ...

(Copy an item and send the copies to every block that it’s linked to) Unlike BufferBlock, BroadcastBlock’s mission in life is to enable all targets linked from the block to get a copy of every element published, continually overwriting the “current” value with those propagated to it. Additionally,...

(Collects a certain number of total items from 2-3 inputs and groups them into a Tuple of collections of data items) BatchedJoinBlock<T1, T2,…> is in a sense a combination of BatchBlock and JoinBlock<T1, T2,…>. Whereas JoinBlock<T1, T2,…> is used to aggregate one input from each ...

(Select, one-to-one) As with ActionBlock, TransformBlock<TInput, TOutput> enables the execution of a delegate to perform some action for each input datum; unlike with ActionBlock, this processing has an output. This delegate can be a Func<TInput, TOutput>, in which case processing of t...

(foreach) This class can be thought of logically as a buffer for data to be processed combined with tasks for processing that data, with the “dataflow block” managing both. In its most basic usage, we can instantiate an ActionBlock and “post” data to it; the delegate provided at the ActionBlock’s c...

(SelectMany, 1-m: The results of this mapping are “flattened”, just like LINQ’s SelectMany) TransformManyBlock<TInput, TOutput> is very similar to TransformBlock<TInput, TOutput>. The key difference is that whereas a TransformBlock<TInput, TOutput> produces one and only one outpu...

(Groups a certain number of sequential data items into collections of data items) BatchBlock combines N single items into one batch item, represented as an array of elements. An instance is created with a specific batch size, and the block then creates a batch as soon as it’s received that number o...

Dim sites() As String = {"Stack Overflow", "Super User", "Ask Ubuntu", "Hardware Recommendations"} Dim query = From x In sites Where x.StartsWith("S") ' result = "Stack Overflow", "Super User" Query will be enumerable objec...

Dim sites() As String = {"Stack Overflow", "Super User", "Ask Ubuntu", "Hardware Recommendations"} Dim query = From x In sites Select x.Length ' result = 14, 10, 10, 24 Query...

ListView - A core component designed for efficient display of vertically scrolling lists of changing data. The minimal API is to create a ListView.DataSource, populate it with a simple array of data blobs, and instantiate a ListView component with that data source and a renderRow callback which take...

Public Function GetUserFirstName(UserName As String) As String Dim Firstname As String = "" 'Specify the SQL that you want to use including a Parameter Dim SQL As String = "select firstname from users where username=@UserName" 'Provide a Data Sourc...

A stream is an object that provides a low-level means to transfer data. They themselves do not act as data containers. The data that we deal with is in form of byte array(byte []). The functions for reading and writing are all byte orientated, e.g. WriteByte(). There are no functions for dealing w...

Java and most other languages store negative integral numbers in a representation called 2's complement notation. For a unique binary representation of a data type using n bits, values are encoded like this: The least significant n-1 bits store a positive integral number x in integral representati...

Variables are SHADOWED and methods are OVERRIDDEN. Which variable will be used depends on the class that the variable is declared of. Which method will be used depends on the actual class of the object that is referenced by the variable. class Car { public int gearRatio = 8; public St...

Casting an instance of a base class to a subclass as in : b = (B) a; is called narrowing (as you are trying to narrow the base class object to a more specific class object) and needs an explicit type-cast. Casting an instance of a subclass to a base class as in: A a = b; is called widening and does...

If we try to change an object on the UI thread from a different thread we will get a cross-thread operation exception: Private Sub Button_Click(sender As Object, e As EventArgs) Handles MyButton.Click ' Cross thread-operation exception as the assignment is executed on a different thread '...

Random and ThreadLocalRandom are good enough for everyday use, but they have a big problem: They are based on a linear congruential generator, an algorithm whose output can be predicted rather easily. Thus, these two classes are not suitable for cryptographic uses (such as key generation). One can ...

Drag 1 textbox and 1 button Double click the button1 and you will be transferred to the Button1_Click event Public Class Form1 Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click End Sub End Class Type the name of the object that you want to target, ...