Tutorial by Examples: e

int main (void) { const int foo_readonly = 10; int *foo_ptr; foo_ptr = (int *)&foo_readonly; /* (1) This casts away the const qualifier */ *foo_ptr = 20; /* This is undefined behavior */ return 0; } Quoting ISO/IEC 9899:201x, section 6.7.3 §2: If an attempt i...

Format strings may contain named placeholders that are interpolated using keyword arguments to format. Using a dictionary (Python 2.x) >>> data = {'first': 'Hodor', 'last': 'Hodor!'} >>> '{first} {last}'.format(**data) 'Hodor Hodor!' Using a dictionary (Python 3.2+) >&gt...

installing npm install web-component-tester --save-dev setting up wct.conf.js module.exports = { verbose: true, plugins: { local: { browsers: ['chrome'] } } }; running node node_modules/web-component-tester/bin/wct test/index.html <html...

A variable declared constexpr is implicitly const and its value may be used as a constant expression. Comparison with #define A constexpr is type-safe replacement for #define based compile-time expressions. With constexpr the compile-time evaluated expression is replaced with the result. For examp...

Ada is a programming language for which there exists multiple compilers. One of these compilers, and perhaps the most used, is GNAT. It is part of the GCC toolchain. It can be installed from several sources: The yearly GPL release done by AdaCore, available for free on libre site. This ver...

Note: This example is based on the Oracle JVM implementation. Built-in tools like jmap, jconsole, and jvisualvm are available in a JDK and can be used to generate and analyze heap memory dumps taken from a running JVM application. However, one option to generate a heap dump without using JDK tools ...

class Foldable t where {-# MINIMAL foldMap | foldr #-} foldMap :: Monoid m => (a -> m) -> t a -> m foldMap f = foldr (mappend . f) mempty foldr :: (a -> b -> b) -> b -> t a -> b foldr f z t = appEndo (foldMap (Endo #. f) t) z -- and a nu...

class (Functor t, Foldable t) => Traversable t where {-# MINIMAL traverse | sequenceA #-} traverse :: Applicative f => (a -> f b) -> t a -> f (t b) traverse f = sequenceA . fmap f sequenceA :: Applicative f => t (f a) -> f (t a) sequenceA = t...

<?xml version="1.0" encoding="UTF-8"?> <Configuration> <Appenders> <Console name="STDOUT" target="SYSTEM_OUT"> <PatternLayout pattern="%d %-5p [%t] %C{2} %m%n"/> </Console> </Appenders&gt...

A method can take an array parameter and destructure it immediately into named local variables. Found on Mathias Meyer's blog. def feed( amount, (animal, food) ) p "#{amount} #{animal}s chew some #{food}" end feed 3, [ 'rabbit', 'grass' ] # => "3 rabbits chew some gra...

To calculate moving average of salary of the employers based on their role: val movAvg = sampleData.withColumn("movingAverage", avg(sampleData("Salary")) .over( Window.partitionBy("Role").rowsBetween(-1,1)) ) withColumn() creates a new column named m...

Always use Rails.logger.{debug|info|warn|error|fatal} rather than puts. This allows your logs to fit into the standard log format, have a timestamp and have a level so you choose whether they are important enough to be shown in a specific environment. You can see the separate log files for your appl...

By default the Custom Tool property for a VB resource file is VbMyResourcesResXFileCodeGenerator. However, with this code generator the view (XAML) will not be able to access the resources. To solve this problem add Public before the Custom Tool property value. To select the Resources.resx file in ...

Open the resource file by double clicking it. Change the Access Modifier to "Public".

Bean1 @ManagedBean @ViewScoped public class Bean1 implements Serializable { /** * Just takes the given param, sets it into flash context and redirects to * page2 * * @param inputValue * @return */ public String goPage2(String inputValue) { ...

Sometimes you might accidentally run something in the shell that ends up waiting forever, and thus blocking the shell: iex(2)> receive do _ -> :stuck end In that case, press Ctrl-g. You'll see: User switch command Enter these commands in order: k (to kill the shell process) s (to st...

Computed observables are functions that can "watch" or "react" to other observables on the view model. The following example shows how you would display the total number of users and the average age. Note: The example below can also make use of pureComputed() (introduced in v3....

In order to add Firebase Crash Reporting to your app, perform the following steps: Create an app on the Firebase Console here. Copy the google-services.json file from your project into your in app/ directory. Add the following rules to your root-level build.gradle file in order to inc...

You can return an anonymous object from your function public static object FunctionWithUnknowReturnValues () { /// anonymous object return new { a = 1, b = 2 }; } And assign the result to a dynamic object and read the values in it. /// dynamic object dynamic x = FunctionWithUnknowR...

You can return an instance of Tuple class from your function with two template parameters as Tuple<string, MyClass>: public Tuple<string, MyClass> FunctionWith2ReturnValues () { return Tuple.Create("abc", new MyClass()); } And read the values like below: Console.Wri...