Tutorial by Examples: g

PHP's source code is hosted on GitHub. To build from source you will first need to check out a working copy of the code. mkdir /usr/local/src/php-7.0/ cd /usr/local/src/php-7.0/ git clone -b PHP-7.0 https://github.com/php/php-src . If you want to add a feature, it's best to create your own bra...

We can use flatten() in order to lazily reduce the nesting of a multi-dimensional sequence. For example, lazy flattening a 2D array into a 1D array: // A 2D array of type [[Int]] let array2D = [[1, 3], [4], [6, 8, 10], [11]] // A FlattenBidirectionalCollection<[[Int]]> let lazilyFlatten...

Melting: The basics Melting is used to transform data from wide to long format. Starting with a wide data set: DT = data.table(ID = letters[1:3], Age = 20:22, OB_A = 1:3, OB_B = 4:6, OB_C = 7:9) We can melt our data using the melt function in data.table. This returns another data.table in long...

To create a libary , you should use File -> New -> New Module -> Android Library. This will create a basic library project. When that's done, you must have a project that is set up the following manner: [project root directory] [library root directory] [gradle] build.gradle...

To use the library, you must include it as a dependency with the following line: compile project(':[library root directory]')

PubNub Access Manager (PAM) extends PubNub's existing security framework by allowing developers to create and enforce secure access to channels throughout the PubNub Real Time Network. Access Manager allows you to manage granular permissions for your realtime apps and data streams, create multiple ...

fn copy_if<F>(slice: &[i32], pred: F) -> Vec<i32> where for<'a> F: Fn(&'a i32) -> bool { let mut result = vec![]; for &element in slice { if pred(&element) { result.push(element); } } result } This s...

Add the [Serializable] attribute to mark an entire object for binary serialization: [Serializable] public class Vector { public int X; public int Y; public int Z; [NonSerialized] public decimal DontSerializeThis; [OptionalField] public string Name; } All...

If you use the [NonSerialized] attribute, then that member will always have its default value after deserialization (ex. 0 for an int, null for string, false for a bool, etc.), regardless of any initialization done in the object itself (constructors, declarations, etc.). To compensate, the attribut...

That would get more control over serialization, how to save and load types Implement ISerializable interface and create an empty constructor to compile [Serializable] public class Item : ISerializable { private string _name; public string Name { get { return _name; } ...

Implements a serialization surrogate selector that allows one object to perform serialization and deserialization of another As well allows to properly serialize or deserialize a class that is not itself serializable Implement ISerializationSurrogate interface public class ItemSurrogate : ISerial...

The first element of sys.argv[0] is the name of the python file being executed. The remaining elements are the script arguments. # script.py import sys print(sys.argv[0]) print(sys.argv) $ python script.py => script.py => ['script.py'] $ python script.py fizz => script.py ...

For queries, Realm provides the realmResults.asObservable() method. Observing results is only possible on looper threads (typically the UI thread). For this to work, your configuration must contain the following realmConfiguration = new RealmConfiguration.Builder(context) // ...

In order to dynamically decide what beans to inject, we can use FactoryBeans. These are classes which implement the factory method pattern, providing instances of beans for the container. They are recognized by Spring and can be used transparently, without need to know that the bean comes from a fac...

When referring to gcc's documentation, you should know which version of gcc you are running. The GCC project has a manual for each version of gcc which includes features that are implemented in that version. Use the '-v' option to determine the version of gcc you are running. gcc -v Example Ou...

Some languages have a native structure for sets. To make a set in Go, it's best practice to use a map from the value type of the set to an empty struct (map[Type]struct{}). For example, with strings: // To initialize a set of strings: greetings := map[string]struct{}{ "hi": {}, ...

Sometimes you want to have a file held in Git but ignore subsequent changes. Tell Git to ignore changes to a file or directory using update-index: git update-index --assume-unchanged my-file.txt The above command instructs Git to assume my-file.txt hasn't been changed, and not to check or repor...

Starting the Erlang shell On a UNIX system you start the Erlang shell from a command prompt with the command erl Example: $ erl Erlang/OTP 18 [erts-7.0] [source] [64-bit] [smp:8:8] [async-threads:10] [hipe] [kernel-poll:false] Eshell V7.0 (abort with ^G) 1> The text that shows when y...

Environment variables that affect the go tool can be viewed via the go env [var ...] command: $ go env GOARCH="amd64" GOBIN="/home/yourname/bin" GOEXE="" GOHOSTARCH="amd64" GOHOSTOS="linux" GOOS="linux" GOPATH="/home/yourname&q...

If Go is not pre-installed in your system you can go to https://golang.org/dl/ and choose your platform to download and install Go. To set up a basic Go development environment, only a few of the many environment variables that affect the behavior of the go tool (See: Listing Go Environment Variabl...