Search results
Results from the WOW.Com Content Network
The LaTeX source code is attached to the PDF file (see imprint). ... Description ={{en|1=pdf version of english wikibook on regular expressions}} ...
A regular expression (shortened as regex or regexp), [1] sometimes referred to as rational expression, [2] [3] is a sequence of characters that specifies a match pattern in text. Usually such patterns are used by string-searching algorithms for "find" or "find and replace" operations on strings , or for input validation .
For example, a bare namespace returns the pages of the namespace. The query term1 term2 regexp relies heavily on the first two terms to reduce the search domain size. All terms in a query are indexed searches unless they are a regexp. Indexed terms run word-wise instantly, and a regexp runs character-wise slowly. Even the most basic use of a ...
A regex search scans the text of each page on Wikipedia in real time, character by character, to find pages that match a specific sequence or pattern of characters. Unlike keyword searching, regex searching is by default case-sensitive, does not ignore punctuation, and operates directly on the page source (MediaWiki markup) rather than on the ...
-word will not the term, excluding the pages that match word.!word will not the term (similarly) Logical OR increases results, whereas logical AND decreases them. Logical not is a good way to refine a query by removing any kind of term except the prefix parameter. For example while -refining -unwanted search results.
Regular Expression Flavor Comparison – Detailed comparison of the most popular regular expression flavors; Regexp Syntax Summary; Online Regular Expression Testing – with support for Java, JavaScript, .Net, PHP, Python and Ruby; Implementing Regular Expressions – series of articles by Russ Cox, author of RE2; Regular Expression Engines
Perl Compatible Regular Expressions (PCRE) is a library written in C, which implements a regular expression engine, inspired by the capabilities of the Perl programming language. Philip Hazel started writing PCRE in summer 1997. [ 3 ]
Common applications of approximate matching include spell checking. [5] With the availability of large amounts of DNA data, matching of nucleotide sequences has become an important application. [1] Approximate matching is also used in spam filtering. [5] Record linkage is a common application where records from two disparate databases are matched.