Tutorial by Examples: com

Common Lisp Quick Reference

The Common Lisp Quick Reference is a document which can be printed and bound as a booklet in various layouts to have a printed quick reference for Common Lisp.

common-lisp • ANSI Common Lisp, the language standard and its documentation

This will create a composite index of both keys, mystring and mydatetime and speed up queries with both columns in the WHERE clause. CREATE INDEX idx_mycol_myothercol ON my_table(mycol, myothercol) Note: The order is important! If the search query does not include both columns in the WHERE claus...

MySQL • Indexes and Keys

Redis command line interface

redis-cli is the Redis command line interface program that allows to send commands to Redis and read the replies sent by the server, directly from the terminal. Basic command line usage is below: Access to redis: $ redis-cli 127.0.0.1:6379> Access to redis with authentication: $ redis-cli ...

redis • Getting started with redis

Coding style and recommendations

Content has been moved back to good 'ol Servlets wiki page

servlets • Getting started with servlets

Copy to clipboard from textarea using execCommand("copy")

Example: <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title></title> </head> <body> <textarea id="content"></textarea> <input type="button" id="copy...

JavaScript • execCommand and contenteditable

Character class and common problems faced by beginner

1. Character Class Character class is denoted by []. Content inside a character class is treated as single character separately. e.g. suppose we use [12345] In the example above, it means match 1 or 2 or 3 or 4 or 5 . In simple words, it can be understood as or condition for single characters (...

Regular Expressions • Character classes

Moving scroll when UITextView becomes first responder

Observe the notifications UIKeyboardWillShowNotification and UIKeyboardWillHideNotification, update the scrollView content insets according to keyboard height, then scroll to the focused control. - (void)viewDidLoad { [super viewDidLoad]; // register for keyboard notifications [[...

iOS • UITextField

Comments

Comments in XML look like so:  They can appear in element content or top-level: <?xml version="1.0"?>  <document>  </document> Comments canno...

xml • Building blocks

Using std::move to reduce complexity from O(n²) to O(n)

C++11 introduced core language and standard library support for moving an object. The idea is that when an object o is a temporary and one wants a logical copy, then its safe to just pilfer o's resources, such as a dynamically allocated buffer, leaving o logically empty but still destructible and co...

C++ • Move Semantics

Compare operation with collections - Create collections

Compare operation with collections - Create collections 1. Create List DescriptionJDKguavags-collectionsCreate empty listnew ArrayList<>()Lists.newArrayList()FastList.newList()Create list from valuesArrays.asList("1", "2", "3")Lists.newArrayList("1", &...

Java Language • Alternative Collections

Combining two arrays (keys from one, values from another)

The following example shows how to merge two arrays into one associative array, where the key values will be the items of the first array, and the values will be from the second: $array_one = ['key1', 'key2', 'key3']; $array_two = ['value1', 'value2', 'value3']; $array_three = array_combine($ar...

PHP • Processing Multiple Arrays Together

Adding Components

A component is some sort of user interface element, such as a button or a text field. Creating a Component Creating components is near identical to creating a window. Instead of creating a JFrame however, you create that component. For example, to create a JButton, you do the following. JButton b...

swing • Using Swing for Graphical User Interfaces

Setting Parameters for Components

Components have various parameters that can be set for them. They vary from component to component, so a good way to see what parameters can be set for components is to start typing componentName.set, and let your IDE's autocomplete (If you use an IDE) suggest methods. The default shortcut in many I...

swing • Using Swing for Graphical User Interfaces

Common Components

DescriptionClassButtonJButtonCheckboxJCheckBoxDrop down menu / Combo boxJComboBoxLabelJLabelListJListMenu barJMenuBarMenu in a menu barJMenuItem in a menuJMenuItemPanelJPanelProgress barJProgressBarRadio buttonJRadioButtonScroll barJScrollBarSliderJSliderSpinner / Number pickerJSpinnerTableJTableTre...

swing • Using Swing for Graphical User Interfaces

All combinations of dictionary values

options = { "x": ["a", "b"], "y": [10, 20, 30] } Given a dictionary such as the one shown above, where there is a list representing a set of values to explore for the corresponding key. Suppose you want to explore "x"="a" w...

Python Language • Dictionary

Common examples of JSON objects, with related (Java) object counterparts

Throughout this example it is assumed that the 'root' object that is being serialized to JSON is an instance of the following class : public class MyJson { } Example 1 : An example of an instance of MyJson, as is: {} i.e. since the class has no fields, only curly brackets are serialized...

JSON • Getting started with JSON

Dispatching completion block on a custom thread

Whenever AFNetworking is used the call is dispatched on a custom thread provided by AFNetworking. When the call returns to the completion block, it gets executed on the main thread. This example sets a custom thread that dispatch to the completion block: AFNetworking 2.xx: // Create dispatch_queu...

iOS • AFNetworking

Convert NSDate that is composed from hour and minute (only) to a full NSDate

There are many cases when one has created an NSDate from only an hour and minute format, i.e: 08:12 that returns from a server as a String and you initiate an NSDate instance by these values only. The downside for this situation is that your NSDate is almost completely "naked" and what yo...

iOS • NSDate

Installing for Command Line Use

ANTLR is distributed as a Java Jar file It can be downloaded here. As ANTLR is compiled as a jar file it subsequently requires the Java runtime environment to operate, if you do not have It can be downloaded here. Once the ANTLR JAR file has been downloaded you can run ANTLR from the command line i...

ANTLR • Introduction to ANTLR v4

Array size: type safe at compile time.

#include <stddef.h> // size_t, ptrdiff_t //----------------------------------- Machinery: using Size = ptrdiff_t; template< class Item, size_t n > constexpr auto n_items( Item (&)[n] ) noexcept -> Size { return n; } //----------------------------------- Us...

C++ • Arrays