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CommonJS is a popular modularization pattern that's used in Node.js. The CommonJS system is centered around a require() function that loads other modules and an exports property that lets modules export publicly accessible methods. Here's an example of CommonJS, we'll load Lodash and Node.js' fs m...

Iterator methods can be broken into two distinct groups: Adapters Adapters take an iterator and return another iterator // Iterator Adapter // | | let my_map = (1..6).map(|x| x * x); println!("{:?}", my_map); Output Map { iter: 1..6 } Note that the v...

For functions that need to take a collection of objects, slices are usually a good choice: fn work_on_bytes(slice: &[u8]) {} Because Vec<T> and arrays [T; N] implement Deref<Target=[T]>, they can be easily coerced to a slice: let vec = Vec::new(); work_on_bytes(&vec); le...

The following method call enables usage of many advanced features such as sorting, filtering, and exporting data. alv->get_functions( )->set_all( ).

Suppose you have a parentView into which you want to insert a new subView programmatically (eg. when you want to insert an UIImageView into a UIViewController's view), than you can do it as below. Objective-C [parentView addSubview:subView]; Swift parentView.addSubview(subView) You can also...

Formats results of SELECT query as JSON text. FOR JSON PATH clause is added after query: SELECT top 3 object_id, name, type, principal_id FROM sys.objects FOR JSON PATH Column names will be used as keys in JSON, and cell values will be generated as JSON values. Result of the query would be an a...

FOR JSON PATH enables you to control format of the output JSON using column aliases: SELECT top 3 object_id as id, name as [data.name], type as [data.type] FROM sys.objects FOR JSON PATH Column alias will be used as a key name. Dot-separated column aliases (data.name and data.type) will be gen...

WITHOUT_ARRAY_WRAPPER option enables you to generate a single object instead of the array. Use this option if you know that you will return single row/object: SELECT top 3 object_id, name, type, principal_id FROM sys.objects WHERE object_id = 3 FOR JSON PATH, WITHOUT_ARRAY_WRAPPER Single obje...

Automatically nests values from the second table as a nested sub-array of JSON objects: SELECT top 5 o.object_id, o.name, c.column_id, c.name FROM sys.objects o JOIN sys.columns c ON o.object_id = c.object_id FOR JSON AUTO Result of the query would be array of JSON objects: [ { &...

If you need some complex JSON structure that cannot be created using FOR JSON PATH or FOR JSON AUTO, you can customize your JSON output by putting FOR JSON sub-queries as column expressions: SELECT top 5 o.object_id, o.name, (SELECT column_id, c.name FROM sys.columns c WHERE o...

TOP clause returns only first N rows in the result: SELECT TOP 10 * FROM sys.objects

OFFSET FETCH clause is more advanced version of TOP. It enables you to skip N1 rows and take next N2 rows: SELECT * FROM sys.objects ORDER BY object_id OFFSET 50 ROWS FETCH NEXT 10 ROWS ONLY You can use OFFSET without fetch to just skip first 50 rows: SELECT * FROM sys.objects ORDER BY obj...

@Singleton @Component(modules = AppModule.class) public interface AppComponent { void inject(App app); Context provideContext(); Gson provideGson(); MainActivityComponent mainActivityComponent(ActivityModule activityModule); } @ActivityScope @Subcomponent(modules = Act...

This technique details how to ensure that your .apk has been signed with your developer certificate, and leverages the fact that the certificate remains consistent and that only you have access to it. We can break this technique into 3 simple steps: Find your developer certificate signature. Em...

We want to gather data created by multiple Workers. First we create a Queue: sink = Queue.new Then 16 workers all generating a random number and pushing it into sink: (1..16).to_a.map do Thread.new do sink << rand(1..100) end end.map(&:join) And to get the data, conver...

We want to process data in parallel. Let's populate source with some data: source = Queue.new data = (1..100) data.each { |e| source << e } Then create some workers to process data: (1..16).to_a.map do Thread.new do until source.empty? item = source.pop sleep 0.5 ...

We want to process data in parallel and push it down the line to be processed by other workers. Since Workers both consume and produce data we have to create two queues: first_input_source = Queue.new first_output_sink = Queue.new 100.times { |i| first_input_source << i } First wave of...

syncer = Queue.new a = Thread.new do syncer.pop puts "this happens at end" end b = Thread.new do puts "this happens first" STDOUT.flush syncer << :ok end [a, b].map(&:join)

q = Queue.new q << 1 q << 2 a = Array.new a << q.pop until q.empty? Or a one liner: [].tap { |array| array < queue.pop until queue.empty? }

Enum constructors can be matched using pattern matching. Assume the following enum: enum Color { Red; Green; Blue; RGB(r : Int, g : Int, b : Int); } Colours with only a green channel value can be matched as follows: var color = Color.RGB(0, 127, 0); var isGreenOnly = swit...