Tutorial by Examples: o

C++11 void_t is a meta-function that maps any (number of) types to type void. The primary purpose of void_t is to facilitate writing of type traits. std::void_t will be part of C++17, but until then, it is extremely straightforward to implement: template <class...> using void_t = void; ...

C++11 One of constraining function is to use trailing decltype to specify the return type: namespace details { using std::to_string; // this one is constrained on being able to call to_string(T) template <class T> auto convert_to_string(T const& val, int ) ->...

main.rs extern crate serde; extern crate serde_json; // Import this crate to derive the Serialize and Deserialize traits. #[macro_use] extern crate serde_derive; #[derive(Serialize, Deserialize, Debug)] struct Point { x: i32, y: i32, } fn main() { let point = Point { x: ...

An example document class that prints “Hello, World” to the debug console when instantiated. import flash.display.Sprite; public class Main extends Sprite { public function Main() { super(); trace("Hello, World"); } }

fn main() { let maybe_cake = Some("Chocolate cake"); let not_cake = None; // The unwrap method retrieves the value from the Option // and panics if the value is None println!("{}", maybe_cake.unwrap()); // The expect method works much like the un...

A React component can be defined as an ES6 class that extends the base React.Component class. In its minimal form, a component must define a render method that specifies how the component renders to the DOM. The render method returns React nodes, which can be defined using JSX syntax as HTML-like ta...

What is a node.js module (link to article): A module encapsulates related code into a single unit of code. When creating a module, this can be interpreted as moving all related functions into a file. Now lets see an example. Imagine all files are in same directory: File: printer.js "use...

The Default keyword is used to execute an action when no other conditions match the input value. Example: switch('Condition') { 'Skip Condition' { 'First Action' } 'Skip This Condition Too' { 'Second Action' } Default { 'Default Action' } } Output: D...

Fixnum#to_s takes an optional base argument and represents the given number in that base: 2.to_s(2) # => "10" 3.to_s(2) # => "11" 3.to_s(3) # => "10" 10.to_s(16) # => "a" If no argument is provided, then it represents the number in bas...

Compile errors can be generated using the preprocessor. This is useful for a number of reasons some of which include, notifying a user if they are on an unsupported platform or an unsupported compiler. e.g. Return Error if gcc version is 3.0.0 or earlier. #if __GNUC__ < 3 #error "This cod...

The Arbitrary class is for types that can be randomly generated by QuickCheck. The minimal implementation of Arbitrary is the arbitrary method, which runs in the Gen monad to produce a random value. Here is an instance of Arbitrary for the following datatype of non-empty lists. import Test.QuickC...

% Define serial port with a baud rate of 115200 rate = 115200; if ispc s = serial('COM1', 'BaudRate',rate); elseif ismac % Note that on OSX the serial device is uniquely enumerated. You will % have to look at /dev/tty.* to discover the exact signature of your % serial device ...

Assuming you created the serial port object s as in this example, then % Read one byte data = fread(s, 1); % Read all the bytes, version 1 data = fread(s); % Read all the bytes, version 2 data = fread(s, s.BytesAvailable); % Close the serial port fclose(s);

Assuming you created the serial port object s as in this example, then to close it fclose(s) However, sometimes you can accidentally lose the port (e.g. clear, overwrite, change scope, etc...), and fclose(s) will no longer work. The solution is easy fclose(instrfindall) More info at instrfin...

Assuming you created the serial port object s as in this example, then % Write one byte fwrite(s, 255); % Write one 16-bit signed integer fwrite(s, 32767, 'int16'); % Write an array of unsigned 8-bit integers fwrite(s,[48 49 50],'uchar'); % Close the serial port fclose(s);

As there is currently no simple way of combining dictionaries in Swift, it can be useful to overload the + and += operators in order to add this functionality using generics. // Combines two dictionaries together. If both dictionaries contain // the same key, the value of the right hand side dicti...

The SQL 2008 standard defines the FETCH FIRST clause to limit the number of records returned. SELECT Id, ProductName, UnitPrice, Package FROM Product ORDER BY UnitPrice DESC FETCH FIRST 10 ROWS ONLY This standard is only supported in recent versions of some RDMSs. Vendor-specific non-stand...

When NSLog is asked to print empty string, it omits the log completely. NSString *name = @""; NSLog(@"%@", name); // Resolves to @"" The above code will print nothing. It is a good practice to prefix logs with labels: NSString *name = @""; NSLog(@&quo...

The for clause of a list comprehension can specify more than one variable: [x + y for x, y in [(1, 2), (3, 4), (5, 6)]] # Out: [3, 7, 11] [x + y for x, y in zip([1, 3, 5], [2, 4, 6])] # Out: [3, 7, 11] This is just like regular for loops: for x, y in [(1,2), (3,4), (5,6)]: print(x+y) ...

Pojo Model public class Model { private String firstName; private String lastName; private int age; /* Getters and setters not shown for brevity */ } Example: String to Object Model outputObject = objectMapper.readValue( "{\"firstName\":\"J...