WEB Developer's Glossary



Alphabetical Jump into Glossary

Symbols  A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z            Back to Parent         Site Conventions         Topic Indices



G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G

• Garbage Collection: JavaScript Memory
The term garbage collection refers to the JS process of removing unneeded variables and there related data from memory. Typically the memory occupied by strings, functions, objects and arrays can be reclaimed for further use. Recall that to access the data for these data types will all require a reference type. The reference type is a pointer into the heap where the actual data exists. JS will keep track of the references for each object (generic object) in the heap. The JS technique of tracking reference types is called "mark-and-sweep". This technique is complex and implementation specific. Suffice it to say, that the JS interpreter knows when all references to an object are void (non-operable) and thusly, the memory space for the related object can be reused.

• Generated Content: CSS Term
Generated content is content that does not come from the document tree (separate from the document language). CSS includes lists and their related properties in the generated content style group. Besides lists, CSS provides two additional features for rendering generated content:
  • the pseudo-elements :before and :after - These selectors allow you to place generated content before or after the element's content.
  • the content property is specified with the :before and :after selectors to place it's generated content into the documents markup.


• Generated Content Style Group: CSS Property
The generated content style group is one of eleven property style groups that help define the total CSS property set. Generated content encompasses lists and the 'content' property. The 'content' property facilitates the insertion of quotes, counters, URI and strings into actual document content. The 'content' property works with the counter properties to bind and render counters. Likewise, the 'content' property works with the 'quotes' property to bind and render quotation symbols. The complete list of properties that comprise this group are:

• Global Flag: JavaScript RegExp
The optional global flag is one of three flags (or modifiers) provided with JavaScript regular expressions. The global flag forces the regular expression processor to continue the search on the target string until the string has been examined from beginning to end. The search will continue regardless of whether the pattern has resulted in a match.

• Global Object: JavaScript Built-in Object
The Global object is one of two JS built-in objects. The Global and the Math objects are not classes. Built-in objects are present at the start of the execution of an ECMAScript program. There members are static and have global scope. The Global object acts as a placeholder for all global properties and global functions. It is a nameless placeholder. We use the term "global" for discussion purposes. However, "Global" is not used to access it's members. The members of the Global object all have there own individual reference identifiers. The members of the Global object are always on the scope chain and at the top of the scope chain unless a function is currently executing. All variables declared at top-level code become properties of the Global object.

• Global Scope: JavaScript Variable
Variables that are visible from anywhere in a program are said to have global scope. Variables that are declared at top level (outside of a function) will have a global scope. Variables that are declared within the function body will have local scope. Variables that are declared implicitly (not specifying the var keyword) will always have global scope. A function name declared at "top level" will have global scope. A nested function has local scope since it is visible only to the function that is one level up in the nesting chain.

• GMT (Greenwich Mean Time): JavaScript Date & Time
Greenwich Mean Time is an older standard of precision time setting based on a solar reading from the Greenwich meridian. It is still correctly referred to as a time zone in the United Kingdom but GMT was replaced as the international time reference by UTC (Coordinated Universal Time).

• Greater Than and Greater Than or Equal Operators: JavaScript Operator
The greater than operators ( symbols: > and >= ) are binary operators with either number or string operands. The greater than operator evaluates to true when its first operand is greater than its second operand. Otherwise, it evaluates to false. Numbers are compared numerically. Strings are compared based on character ASCII values.
The attributes of this operator are:

• Greedy Quantifier: JavaScript RegExp
Repetition quantifiers are inherently greedy. They match the maximum number of occurrences of a pattern that satisfy the regular expression. The greedy quantifier will loop through the string, eliminating the last character of the string with each loop until the string has been exhausted or until a match occurs. Placing a question mark after another quantifier makes the regular expression non-greedy (reluctant).

• Grouping Operator: JavaScript Expression
The grouping operator is a set of parentheses. The use of the parentheses are analogous to algebraic expressions. That is, they are used to group related terms of an expression. These grouped expressions can be nested where inner groups evaluate first. A common use of the grouping operator is to override the normal precedence of operations within an expression. The grouping operator is a totally different feature from the parentheses operator that is used in the function call statement.

• Grouping Patterns: JavaScript RegExp
Grouping patterns are designated by enclosing a group of literal characters, character classes and/or repetition quantifiers inside parentheses. When the pattern contains one or more characters that repeat themselves, they may be specified only once as a group. For instance, a pattern with repeating characters like "catcatcat" can be specified in a group "(cat) {3}". Notice the number within curly braces sets the repeat number.

• Grouping Selectors: CSS Selector
Serveral selectors may be grouped into a comma-separated list when they share the same style declarations. By compacting common styles into a group, a web designer can reduce the size of the style sheet and centralize styles thereby making style maintanence and control much simplier. The grouping of selectors is one of the CSS shorthand mechanisms. h1, h2, h3, h4, h5, h6, p.blue-font { color: #000080; } /*six type selector and one class selector as a group*/















Top            

Rx4AJAX        About Us | CSS Index | JS Index | HTML Index | Contact Us | Privacy Policy | Built By PPThompson: 2008