Search results
Results from the WOW.Com Content Network
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 ...
Matches any single character (many applications exclude newlines, and exactly which characters are considered newlines is flavor-, character-encoding-, and platform-specific, but it is safe to assume that the line feed character is included). Within POSIX bracket expressions, the dot character matches a literal dot.
In SQL, wildcard characters can be used in LIKE expressions; the percent sign % matches zero or more characters, and underscore _ a single character. Transact-SQL also supports square brackets ([and ]) to list sets and ranges of characters to match, a leading caret ^ negates the set and matches only a character not within the list.
The percent sign (%) matches zero or more characters and the underscore (_) matches exactly one. Many implementations of SQL have extended the LIKE operator to allow a richer pattern-matching language, incorporating character ranges ([…]), their negation, and elements of regular expressions. [15]
In computer science, an algorithm for matching wildcards (also known as globbing) is useful in comparing text strings that may contain wildcard syntax. [1] Common uses of these algorithms include command-line interfaces, e.g. the Bourne shell [2] or Microsoft Windows command-line [3] or text editor or file manager, as well as the interfaces for some search engines [4] and databases. [5]
A metacharacter is a character that has a special meaning to a computer program, such as a shell interpreter or a regular expression (regex) engine.. In POSIX extended regular expressions, there are 14 metacharacters that must be escaped — preceded by a backslash (\) — in order to drop their special meaning and be treated literally inside an expression: opening and closing square brackets ...
The royal kids might not be allowed to keep some of their Christmas presents from the public this year thanks to the family's strict rules about gift giving.
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