Wide range of in-depth information
                Themes: Default |White |Blue |Green |Orange
                Font Size: Default |Small |Medium |Large

Welcome to, the Regular Expression Library on the internet. Currently we have huge amount of examples. We hope you'll find this site useful and come back whenever you need help writing an expression, you're looking for an expression for a particular task, or are ready to contribute new expressions you堪ust figured out. Thanks!

In February 28, 1927, registered in replica watches uk 4 different languages by the name of rolex replica Hans was divided into oyster, namely Huitre (French), Auster (German), Ostica (Italian) and Ostra (Spanish).Oyster shell is composed of four parts of the structure, the frame is eight sided, inside a screw barrel of replica watches a barrel shaped circle, and the back cover are made by rotating the locking way and the screw barrel to the link, and then spin to die in the octagonal frame


In computing, regular expressions provide a concise and flexible means for identifying strings of text of interest, such as particular characters, words, or patterns of characters.
Regular expressions (abbreviated as regex or regexp, with plural forms regexes, regexps, or regexen) are written in a formal language that can be interpreted by a regular expression processor, a program that either serves as a parser generator or examines text and identifies parts that match the provided specification.

The following examples illustrate a few specifications that could be expressed in a regular expression:

* the sequence of characters "car" in any context, such as "car", "cartoon", or "bicarbonate"
* the word "car" when it appears as an isolated word
* the word "car" when preceded by the word "blue" or "red"
* a dollar sign immediately followed by one or more digits, and then optionally a period and exactly two more digits

Regular expressions can be much more complex than these examples.

Regular expressions are used by many text editors, utilities, and programming languages to search and manipulate text based on patterns. For example, Perl, Ruby and Tcl have a powerful regular expression engine built directly into their syntax. Several utilities provided by Unix distributionsuding the editor ed and the filter grep岥 the first to popularize the concept of regular expressions.

As an example of the syntax, the regular expression \bex can be used to search for all instances of the string "ex" that occur after word boundaries (signified by the \b). Thus in the string "Texts for experts," \bex matches the "ex" in "experts" but not in "Texts" (because the "ex" occurs inside a word and not immediately after a word boundary).

Many modern computing systems provide wildcard characters in matching filenames from a file system. This is a core capability of many command-line shells and is also known as globbing. Wildcards differ from regular expressions in that they generally only express very limited forms of alternatives.