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10 Java Regular Expression Examples You Should Know. Regular expression is an art of the programing, it’s hard to debug , learn and understand, but the powerful features are still attract many developers to code regular expression. Let’s explore the following 10 practical regular expression ~ enjoy :) 1. Username Regular Expression Pattern ^ # Start of the line [a-z0-9_-] # Match characters and symbols in the list, a-z, 0-9 , underscore , hyphen {3,15} # Length at least 3 characters and maximum length of 15 $ # End of the line ==> See the explanation and example here 2.

Computability theory. Computability theory, also called recursion theory, is a branch of mathematical logic, of computer science, and of the theory of computation that originated in the 1930s with the study of computable functions and Turing degrees.

Computability theory

The basic questions addressed by recursion theory are "What does it mean for a function on the natural numbers to be computable? " and "How can noncomputable functions be classified into a hierarchy based on their level of noncomputability? ". The answers to these questions have led to a rich theory that is still being actively researched. The field has since grown to include the study of generalized computability and definability. Invention of the central combinatorial object of recursion theory, namely the Universal Turing Machine, predates and predetermines the invention of modern computers. Recursion theory overlaps with proof theory, effective descriptive set theory, model theory, and abstract algebra. Computability logic. Introduced by Giorgi Japaridze in 2003, computability logic is a research programme and mathematical framework for redeveloping logic as a systematic formal theory of computability, as opposed to classical logic which is a formal theory of proof.

Computability logic

In this approach logical formulas represent computational problems (or, equivalently, computational resources), and their validity means being "always computable". Computational problems and resources are understood in their most general - interactive sense. They are formalized as games played by a machine against its environment, and computability means existence of a machine that wins the game against any possible behavior by the environment. Defining what such game-playing machines mean, computability logic provides a generalization of the Church-Turing thesis to the interactive level. Beautiful JavaScript: Easily Create Chainable (Cascading) Methods for Expressiveness. (Part of the “12 Powerful JavaScript Tips” Series) Prerequisites: — Understand JavaScript’s “this” With Ease — JavaScript Objects in Detail Chaining Methods, also known as Cascading, is the technique of repeatedly calling different methods (or the same method) on an object in one continuous line of code.

Beautiful JavaScript: Easily Create Chainable (Cascading) Methods for Expressiveness

This technique is popular in jQuery and other JavaScript libraries, and it is even inherent in JavaScript’s native methods like the common String methods. The expressiveness of writing this: $("#wrapper").fadeOut().html("Welcome, Sir").fadeIn(); 16 JavaScript Concepts JavaScript Professionals Must Know Well. (Essential JavaScript Concepts for Modern JavaScript Development ) If you plan to work as JavaScript Professional, you must know some JavaScript concepts and JavaScript-related web-development technologies, particularly as a modern JavaScript developer.

16 JavaScript Concepts JavaScript Professionals Must Know Well

If you know the 16 concepts enumerated below, you have the skill necessary to build world-class modern JavaScript web applications, and you are set for the near future—0 to 3 years. XML APIs for databases. Databases and XML offer complementary functionality for storing data.

XML APIs for databases

Databases store data for efficient retrieval, whereas XML offers an easy information exchange that enables interoperability between applications. To take advantage of XML's features we can convert database tables into XML documents. We can then use XML tools with such documents for further processing. For example, XML documents can be presented as HTML pages with XSLT stylesheets, can be searched with XML-based query languages such as XQL, can be used as a data-exchange format, and so on.

However, converting a database into an XML document is an expensive approach, one that requires not only the initial cost of conversion but also the subsequent costs of synchronizing both information sources. Alternatives To Regular Expressions. Taking "alternative" to mean "semantically equivalent facility with different syntax", there are at least these alternatives to/with RegularExpressions: Basic regular expressions "Extended" regular expressions Perl-compatible regular expressions ... and many other variants...

Alternatives To Regular Expressions

SNOBOL-style RE syntax (SnobolLanguage, IconLanguage) SRE syntax (RE's as EssExpressions) different FSM syntaces Finite-state intersection grammars (quite expressive) ParsingExpressionGrammars? , as in OMetaLanguage and LuaLanguage ( The parse mode of RebolLanguage ProbabilityBasedParsing ParsingWithDerivatives? Is an interesting approach. I am not much of a fan of RegularExpressions.

It is too hard to remember what the symbols stand for, for one.

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Regular Expressions: 30 Useful Tools and Resources. Regular expression, or often known as regex, is a pattern that consist of rules used to match a certain set of strings.

Regular Expressions: 30 Useful Tools and Resources

They are extremely powerful, and you’ll need them in most programming languages you come across, especially when there’s a need to scan and match context for further actions. Here’s a simple example of regular expression – to match all string consist of "regular expression", "regular expressions", "regex", and "regexp" in a content, this is your regular expression pattern – reg(ular expression? |ex(p|es)?) Now, they might seem a little bit confusing or hard to pick up at first, but once you understand the syntax, you’ll notice it’s pretty simple and definitely very useful for future coding projects.

Hacker (computer security) Bruce Sterling traces part of the roots of the computer underground to the Yippies, a 1960s counterculture movement which published the Technological Assistance Program (TAP) newsletter.

Hacker (computer security)

[citation needed] TAP was a phone phreaking newsletter that taught techniques for unauthorized exploration of the phone network. Many people from the phreaking community are also active in the hacking community even today, and vice versa. [citation needed] Several subgroups of the computer underground with different attitudes use different terms to demarcate themselves from each other, or try to exclude some specific group with which they do not agree.

According to Ralph D. Semantics (computer science) Formal semantics, for instance, helps to write compilers, better understand what a program is doing and to prove, e.g., that the following if statement if 1 = 1 then S1 else S2 has the same effect as S1 alone.

Semantics (computer science)

The field of formal semantics encompasses all of the following: The definition of semantic modelsThe relations between different semantic modelsThe relations between different approaches to meaningThe relation between computation and the underlying mathematical structures from fields such as logic, set theory, model theory, category theory, etc. There are many approaches to formal semantics; these belong to three major classes: The distinctions between the three broad classes of approaches can sometimes be vague, but all known approaches to formal semantics use the above techniques, or some combination thereof. Programming language. The earliest programming languages preceded the invention of the computer, and were used to direct the behavior of machines such as Jacquard looms and player pianos.[1] Thousands of different programming languages have been created, mainly in the computer field, and many more still are being created every year.

Programming language

Many programming languages require computation to be specified in an imperative form (i.e., as a sequence of operations to perform), while other languages utilize other forms of program specification such as the declarative form (i.e. the desired result is specified, not how to achieve it). Definitions[edit] A programming language is a notation for writing programs, which are specifications of a computation or algorithm.[2] Some, but not all, authors restrict the term "programming language" to those languages that can express all possible algorithms.[2][3] Traits often considered important for what constitutes a programming language include:

Syntax highlighting. Syntax highlighting is a feature of text editors that displays text, especially source code, in different colors and fonts according to the category of terms.[1] This feature facilitates writing in a structured language such as a programming language or a markup language as both structures and syntax errors are visually distinct.

Highlighting does not affect the meaning of the text itself; it is intended only for human readers. Syntax highlighting is a form of secondary notation, since the highlights are not part of the text meaning, but serve to reinforce it. Some editors also integrate syntax highlighting with other features, such as spell checking or code folding, as aids to editing which are external to the language. Practical considerations[edit] Syntax highlighting. Model theory. This article is about the mathematical discipline. For the informal notion in other parts of mathematics and science, see Mathematical model. Model theory recognises and is intimately concerned with a duality: It examines semantical elements (meaning and truth) by means of syntactical elements (formulas and proofs) of a corresponding language.

To quote the first page of Chang and Keisler (1990):[1] universal algebra + logic = model theory. Model theory developed rapidly during the 1990s, and a more modern definition is provided by Wilfrid Hodges (1997): although model theorists are also interested in the study of fields. In a similar way to proof theory, model theory is situated in an area of interdisciplinarity among mathematics, philosophy, and computer science. Set theory. The modern study of set theory was initiated by Georg Cantor and Richard Dedekind in the 1870s. After the discovery of paradoxes in naive set theory, numerous axiom systems were proposed in the early twentieth century, of which the Zermelo–Fraenkel axioms, with the axiom of choice, are the best-known.

Set theory is commonly employed as a foundational system for mathematics, particularly in the form of Zermelo–Fraenkel set theory with the axiom of choice. Beyond its foundational role, set theory is a branch of mathematics in its own right, with an active research community. Contemporary research into set theory includes a diverse collection of topics, ranging from the structure of the real number line to the study of the consistency of large cardinals. History[edit] Georg Cantor. Google Code Search. Google Code Search was a free beta product from Google which debuted in Google Labs on October 5, 2006 allowing web users to search for open-source code on the Internet. Google announced that Code Search was to be shut down along with the Code Search API on January 15, 2012.[1] The service remained online until March 2013,[2] and it now returns a 404. Features included the ability to search using operators. Quantification. Comparison of regular expression engines.

Model theory. Regular Expressions. This section under major construction. Manipulating text (email, web pages, word processing documents, DNA sequences, Java programs) is one of the most basic and important computing tasks. Pattern matching. Quantification. Regular expression. The regular expression(? Recursion (computer science) Recursion in computer science is a method where the solution to a problem depends on solutions to smaller instances of the same problem (as opposed to iteration).[1] The approach can be applied to many types of problems, and recursion is one of the central ideas of computer science.[2] CSS square and rectangle. Nutch. Features[edit] The fetcher ("robot" or "web crawler") has been written from scratch specifically for this project. Xml.fido.gov/stratml/draft/StratMLPart3.xsd.

Simple API for XML. List of XML markup languages. Packages by category. Table of Contents. Boolean algebra. Boolean algebra was introduced by George Boole in his first book The Mathematical Analysis of Logic (1847), and set forth more fully in his An Investigation of the Laws of Thought (1854).[1] According to Huntington the term "Boolean algebra" was first suggested by Sheffer in 1913.[2] Boolean algebra has been fundamental in the development of digital electronics, and is provided for in all modern programming languages. CSS3 . Info - All you ever needed to know about CSS3. Algorithm. Flow chart of an algorithm (Euclid's algorithm) for calculating the greatest common divisor (g.c.d.) of two numbers a and b in locations named A and B.

The algorithm proceeds by successive subtractions in two loops: IF the test B ≥ A yields "yes" (or true) (more accurately the numberb in location B is greater than or equal to the numbera in location A) THEN, the algorithm specifies B ← B − A (meaning the number b − a replaces the old b). Algorithm. Abstract syntax tree. File:Abstract syntax tree for Euclidean algorithm.svg. Abstract syntax tree. Homoiconicity. Homoiconicity. Homoiconicity. Using Cognitive Dimensions in the Classroom as a Discussion Tool for Visual Language Design. Code reuse.

Program comprehension. Software visualization. Abstraction (computer science) Software visualization. Abstraction (computer science) Abstraction (computer science) Notation. Java - Are "while(true)" loops so bad? Databases, Business Data Solutions, Web Scraping Software & Tools - The Data Planet. How to parse web pages using XPath.

Open Market For Internet Content Accessibility. Web scraping. Website Parse Template. Applications. » POS Tagging XML with xGrid and the Stanford Log-linear Part-Of-Speech Tagger Matthew L. Jockers. 2nd Workshop on NLP and XML - Workshop Topics. The while and do-while Statements (The Java™ Tutorials > Learning the Java Language > Language Basics) Read a File and replace a String from Java Program. Java sample code - Replace a line or word in a file - Source code examples. Java sample code - Replace a line or word in a file - Source code examples. How to get text inside span, and use it into other script. Velocity Equivalents - JavaScript Made Easy: Free JavaScripts Tutorials Example Code.

POS tagger (Java. Natural language toolkit : FileHungry Scripts Search. Artificial intelligence : FileHungry Scripts Search. Download Natural Language Toolkit - NLTK, the Natural Language Toolkit, is a suite of program modules, data sets and tutorials supporting research and teaching in computational linguistics and natural language processing. Simple NFC. How to make your own Arduino board. Guidelines for Developing Your Own CSS Framework. Making Modular Layout Systems.

Modern CSS Layouts: The Essential Characteristics. Understanding aside. ZenHTMLSelectorsEn - zen-coding - Selectors and aliases for Zen HTML plugins - Set of plugins for HTML and CSS hi-speed coding. Examples. A better body-class function for WordPress. Sleeping Columns Using the Semantic Grid System. Illustrator: Responsive Design Template.

XML and Java - Parsing XML using Java Tutorial. Free C / C++ Compilers and Interpreters. HTML5 based Floating Menu WYSIWYG editor – Aloha Editor. Aloha Editor–simple and easy to use HTML5 WYSIWYG editor. .JAVA, NET Component Packs for Excel Word PDF PowerPoint Barcode Flash Report. OaK Notepad 1.0 Freeware Download - Development, Text Processing - A notepad project with java. Java Language Conversion Assistant @ SharpToolbox. Speech Recognition By Java - Simplified. Neural network software, stock market & sales forecast - XLPert. Operators for Order based GA by Oga-op - This package has a collection of readily usable genetic operators. Download Personal Identity Management Project Using Java Source Codes, Personal Identity Management Project Using Java Scripts - Java Resource Detector Library by Javaresourcedet, JAVA Dynamic SQL Assistant by J-sql-api and more.

Java AI & NLP Resources (including JavaScript & JSON) Java Libraries. Java Libraries. [Tut] building a kernel. CPU governors explained. The Best Private Server Bot. Selectors. Selectors. Building Mobile Apps with HTML and a Local Database.