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A common pattern in other languages is having a function that produces a "stream" of objects, and being able to use loop-code to loop over it. We can model this in C++ as template<class T> struct generator_iterator { using difference_type=std::ptrdiff_t; using value_type=T; ...

SASS gives you the ability to omit any parameter except the ones you want to overwrite of course. Let's take again the default-box example: @mixin default-box ($color: red, $borderColor: blue) { color: $color; border: 1px solid $borderColor; clear: both; display: block; mar...

Laravel automatically resolves Eloquent models defined in routes or controller actions whose variable names match a route segment name. For example: Route::get('api/users/{user}', function (App\User $user) { return $user->email; }); In this example, since the Eloquent $user variable de...

To register an explicit binding, use the router's model method to specify the class for a given parameter. You should define your explicit model bindings in the boot method of the RouteServiceProvider class public function boot() { parent::boot(); Route::model('user', App\User::class); ...

Deferred execution enables combining different operations to build the final query, before evaluating the values: var list = new List<int>() {1,1,2,3,5,8}; var query = list.Select(x => x + 1); If we execute the query at this point: foreach (var x in query) { Console.Write($"...

With deferred execution, if the data to be queried is changed, the query object uses the data at the time of execution, not at the time of definition. var data = new List<int>() {2, 4, 6, 8}; var query = data.Select(x => x * x); If we execute the query at this point with an immediate m...

Although the @enum macro is quite useful for most use cases, it can be excessive in some use cases. Disadvantages of @enum include: It creates a new type It is a little harder to extend It comes with functionality such as conversion, enumeration, and comparison, which may be superfluous in some...

public class RedisPublisher extends RouteBuilder { public static final String CAMEL_REDIS_CHANNEL = "CamelRedis.Channel"; public static final String CAMEL_REDIS_MESSAGE = "CamelRedis.Message"; @Value("${redis.host}") private String redisHost; ...

public class RedisSubscriber extends RouteBuilder { @Value("${redis.host}") private String redisHost; @Value("${redis.port}") private int redisPort; @Value("${redis.channel.mychannel}") private String redisChannel; private Object b...

<bean id="managedCamel" class="com.pubsub.example.ManagedCamel" > <constructor-arg name="routes"> <list> <ref bean="redisSubscriber"/> </list> </constructor-arg> </bean> &lt...

<bean id="managedCamel" class="com.pubSub.example.ManagedCamel" > <constructor-arg name="routes"> <list> <ref bean="redisPublisher"/> </list> </constructor-arg> </bean> <...

A particular instance of an entity class can be loaded as follows: Foo foo = fooRepository.findOne(id); The findOne method is provided by the CrudRepository interface. It expects an identifier that uniquely identifies an entity instance (for instance, a primary key in a database table). The Java...

All instances of an entity class with one of the class attributes matching a specified value can be retrieved as follows: public interface FooRepository extends CrudRepository<Foo, Long> { List<Foo> findAllByName(String name); } Invoking the findAllByName method results in the JP...

Checking the Existence of Keys Sometimes you may need to check if a key already exists and proceed accordingly. To do so you can use exists() function as shown below: client.exists('key', function(err, reply) { if (reply === 1) { console.log('exists'); } else { cons...

Azure SQL Database has different editions and performance tiers. You can find version, edition (basic, standard, or premium), and service objective (S0,S1,P4,P11, etc.) of SQL Database that is running as a service in Azure using the following statements: select @@version SELECT DATABASEPROPERTYEX...

You can scale-up or scale-down Azure SQL database using ALTER DATABASE statement: ALTER DATABASE WWI MODIFY (SERVICE_OBJECTIVE = 'P6') -- or ALTER DATABASE CURRENT MODIFY (SERVICE_OBJECTIVE = 'P2') If you try to change service level while changing service level of the current database is sti...

You can create a secondary replica of database with the same name on another Azure SQL Server, making the local database primary, and begins asynchronously replicating data from the primary to the new secondary. ALTER DATABASE <<mydb>> ADD SECONDARY ON SERVER <<secondaryserver&gt...

You can put your azure SQL Database in SQL elastic pool: CREATE DATABASE wwi ( SERVICE_OBJECTIVE = ELASTIC_POOL ( name = mypool1 ) ) You can create copy of an existing database and place it in some elastic pool: CREATE DATABASE wwi AS COPY OF myserver.WideWorldImporters ( SERVICE_OBJECTIV...

Prolog features exceptions, which are part of the Prolog ISO standard. An exception can be thrown with throw/1, and caught with catch/3. The ISO standard defines many cases in which errors must or may be thrown. The standardized exceptions are all of the form error(E,_), where E indicates the erro...

gem 'any gem',git: 'any repo',branch: 'specific branch of that repo',ref: 'reference no.' ref specifies individual commit. branch specifies the git branch to pull from.