Tutorial by Examples: g

Determining If Folders and Files Exist

Files: To determine if a file exists, simply pass the filename to the Dir$ function and test to see if it returns a result. Note that Dir$ supports wild-cards, so to test for a specific file, the passed pathName should to be tested to ensure that it does not contain them. The sample below raises an...

VBA • Working With Files and Directories Without Using FileSystemObject

Creating and Deleting File Folders

NOTE: For brevity, the examples below use the FolderExists function from the Determining If Folders and Files Exist example in this topic. The MkDir statement can be used to create a new folder. It accepts paths containing drive letters (C:\Foo), UNC names (\\Server\Foo), relative paths (..\Foo...

VBA • Working With Files and Directories Without Using FileSystemObject

Decoding JSON from Rust enum

This is useful if you use rust in the backend and elm on the front end enum Complex{ Message(String), Size(u64) } let c1 = Complex::Message("hi"); let c2 = Complex::Size(1024u64); The encoded Json from rust will be: c1: {"variant": "Message", ...

Elm Language • Json.Decode

Common quick usage

Regular expressions are often used in methods as parameters to check if other strings are present or to search and/or replace strings. You'll often see the following: string = "My not so long string" string[/so/] # gives so string[/present/] # gives nil string[/present/].nil? # gives ...

Ruby Language • Regular Expressions and Regex Based Operations

Enabling the SecurityManager

Java Virtual Machines (JVMs) can be run with a SecurityManager installed. The SecurityManager governs what the code running in the JVM is allowed to do, based on factors such as where the code was loaded from and what certificates were used to sign the code. The SecurityManager can be installed by ...

Java Language • SecurityManager

Variable leaking in list comprehensions and for loops

Consider the following list comprehension Python 2.x2.7 i = 0 a = [i for i in range(3)] print(i) # Outputs 2 This occurs only in Python 2 due to the fact that the list comprehension “leaks” the loop control variable into the surrounding scope (source). This behavior can lead to hard-to-find...

Python Language • Common Pitfalls

Creating a simple Behavior

To create a Behavior just extend the CoordinatorLayout.Behavior class. Extend the CoordinatorLayout.Behavior Example: public class MyBehavior<V extends View> extends CoordinatorLayout.Behavior<V> { /** * Default constructor. */ public MyBehavior() { ...

Android • CoordinatorLayout and Behaviors

Using the SwipeDismissBehavior

The SwipeDismissBehavior works on any View and implements the functionality of swipe to dismiss in our layouts with a CoordinatorLayout. Just use: final SwipeDismissBehavior<MyView> swipe = new SwipeDismissBehavior(); //Sets the swipe direction for this behavior. ...

Android • CoordinatorLayout and Behaviors

Creating a Stack class with a List Object

Using a list object you can create a fully functional generic Stack with helper methods such as peeking and checking if the stack is Empty. Check out the official python docs for using list as Stack here. #define a stack class class Stack: def __init__(self): self.items = [] ...

Python Language • Stack

Creating a Chat Session and sending a message

Smack (Java) Using Smack 4.1 It is recommended to include Smack as Maven dependency in your project (e.g. by using gradle or Maven). Otherwhise the following Smack artifacts/jars have to be added manually to the classpath: smack-core, smack-extensions, smack-experimental, smack-im, smnack-tcp,...

xmpp • Getting started with xmpp

Connecting from script using password

When you really need to script ssh connection, piping the password into the ssh command does not work (echo passw0rd | ssh host). It is because the password is not read from standard input, but directly from TTY (teleprinter, teletypewriter, Teletype for historical reasons). But there is sshpass to...

Secure Shell • Getting started with Secure Shell

Getting Started

Create a file ckeditor.html with the following content: <!DOCTYPE html> <html> <head> <title>CKEditor Demo!</title> </head> <body> <script src="//cdn.ckeditor.com/4.6.1/basic/ckeditor.js"></script> <div id="e...

ckeditor • Getting started with ckeditor

Computing mean and variance

#include <iostream> #include <boost/accumulators/accumulators.hpp> #include <boost/accumulators/statistics/stats.hpp> #include <boost/accumulators/statistics/mean.hpp> #include <boost/accumulators/statistics/variance.hpp> int main() { using namespace boost...

boost • Boost Accumulators Framework

RMI through JNDI

This example shows how JNDI works in RMI. It has two roles: to provide the server with a bind/unbind/rebind API to the RMI Registry to provide the client with a lookup/list API to the RMI Registry. The RMI Registry is part of RMI, not JNDI. To make this simple, we will use java.rmi.registry....

Java Language • JNDI

Generic Arrays

Generic arrays in Kotlin are represented by Array<T>. To create an empty array, use emptyArray<T>() factory function: val empty = emptyArray<String>() To create an array with given size and initial values, use the constructor: var strings = Array<String>(size = 5, init ...

Kotlin • Arrays

Implementing Currying

One application of closures is to partially apply a function; that is, provide some arguments now and create a function that takes the remaining arguments. Currying is a specific form of partial application. Let's start with the simple function curry(f, x) that will provide the first argument to a ...

Julia Language • Closures

Registering a stream wrapper

A stream wrapper provides a handler for one or more specific schemes. The example below shows a simple stream wrapper that sends PATCH HTTP requests when the stream is closed. // register the FooWrapper class as a wrapper for foo:// URLs. stream_wrapper_register("foo", FooWrapper::class...

PHP • Streams

Using an incremental index

This method works by incrementing an integer from 0 to the greatest index in the array. $colors = ['red', 'yellow', 'blue', 'green']; for ($i = 0; $i < count($colors); $i++) { echo 'I am the color ' . $colors[$i] . '<br>'; } This also allows iterating an array in reverse order wi...

PHP • Array iteration

Using internal array pointers

Each array instance contains an internal pointer. By manipulating this pointer, different elements of an array can be retrieved from the same call at different times. Using each Each call to each() returns the key and value of the current array element, and increments the internal array pointer. ...

PHP • Array iteration

Using foreach

Direct loop foreach ($colors as $color) { echo "I am the color $color<br>"; } Loop with keys $foods = ['healthy' => 'Apples', 'bad' => 'Ice Cream']; foreach ($foods as $key => $food) { echo "Eating $food is $key"; } Loop by reference In the fo...

PHP • Array iteration