Search results
Results from the WOW.Com Content Network
In object-oriented computer programming, a null object is an object with no referenced value or with defined neutral (null) behavior.The null object design pattern, which describes the uses of such objects and their behavior (or lack thereof), was first published as "Void Value" [1] and later in the Pattern Languages of Program Design book series as "Null Object".
In SGML, HTML and XML documents, the logical constructs known as character data and attribute values consist of sequences of characters, in which each character can manifest directly (representing itself), or can be represented by a series of characters called a character reference, of which there are two types: a numeric character reference and a character entity reference.
Incorrect HTML entity escaping may also open up security vulnerabilities for injection attacks such as cross-site scripting. If HTML attributes are left unquoted, certain characters, most importantly whitespace, such as space and tab, must be escaped using entities. Other languages related to HTML have their own methods of escaping characters.
HTML 4 is an SGML application conforming to ISO 8879 – SGML. [20] April 24, 1998 HTML 4.0 [21] was reissued with minor edits without incrementing the version number. December 24, 1999 HTML 4.01 [22] was published as a W3C Recommendation. It offers the same three variations as HTML 4.0 and its last errata [23] were published on May 12, 2001 ...
The table below lists the twenty-five characters defined as whitespace ("WSpace=Y", "WS") characters in the Unicode Character Database. [1] Seventeen use a definition of whitespace consistent with the algorithm for bidirectional writing ("Bidirectional Character Type=WS") and are known as "Bidi-WS" characters.
A numeric character reference (NCR) is a common markup construct used in SGML and SGML-derived markup languages such as HTML and XML. It consists of a short sequence of characters that, in turn, represents a single character. Since WebSgml, XML and HTML 4, the code points of the Universal Character Set (UCS) of Unicode are used.
In HTML 4, there is a standard set of 252 named character entities for characters - some common, some obscure - that are either not found in certain character encodings or are markup sensitive in some contexts (for example angle brackets and quotation marks). Although any Unicode character can be referenced by its numeric code point, some HTML ...
An empty element may be: An empty HTML element, one with tag(s) but no content (HTML element § Empty element) An empty XML element, one with tag(s) but no content (XML § Key terminology) An empty SGML element, one with tag(s) but no content (Standard Generalized Markup Language § EMPTY).