Syntax diagrams

Syntax diagrams indicate the rules and requirements for the XML-based GAS configuration file elements.

These elements may be found in a GAS configuration file (default $FGLASDIR/etc/as.xcf) or in an external application configuration file.

Example: APPLICATION Element Syntax Usage.

This syntax diagram describes the APPLICATION configuration element, its attributes, and its child elements:

<APPLICATION [Id=app-name]  
     Parent=parent-app-name 
     xmlns:xsi=uri 
     xsi:noNamespaceSchemaLocation=schema
    [Abstract={"TRUE"|"FALSE"}] 
    [mode=mode-name]>
   [<DESCRIPTION>...</DESCRIPTION>]
   [<RESOURCE>...</RESOURCE>] [...]
   [<EXECUTION>...</EXECUTION>]
   [<AUTO_LOGOUT>...</AUTO_LOGOUT>] 
   [<UA_OUTPUT>...</UA_OUTPUT>]
</APPLICATION>
  • Configuration elements are written in uppercase within an opening tag ( <ELEMENT_NAME>) and a closing tag ( </ELEMENT_NAME>)
  • If a configuration element has attributes, each attribute consists of an attribute name, followed by an equals sign (=), followed by the attribute value.
    • An attribute name is a string with no spaces. Attribute names are presented in code format.
    • Attribute values are in double quotes. Attribute values presented in code format are exact, and should be used as-is. For example, the attribute Abstract takes a value of either "TRUE" or "FALSE". Attribute values presented as variables expect a string to replace the variable name. For example, the attribute mode expects you to replace "mode_name" with a valid mode name.
    • Attributes appear separated by spaces within the opening tag of the configuration element.
  • Wildcard characters in syntax definitions are usually marked with an underscore. They are used to indicate elements that can either repeat, be mandatory, or be optional.
    Table 1. Wildcard characters
    Wildcards Description
    [ e ] Square braces indicate an optional element in the syntax.
    ... A sign with three dots (ellipsis) indicates that a number of items may appear in a list. If used between an element's opening and closing tags, it indicates one or more child elements may appear.
    [ e1 | e2 ... ] Square braces containing elements separated by a pipe indicate an optional element to be selected from the list.
    { e1 | e2 ... } Curly braces containing elements separated by a pipe indicate a mandatory element to be selected from the list.
    [...] A sign made of square braces with three dots indicate that the previous element can appear more than once.
    [,...] A sign made of square braces with a comma followed by three dots indicate that the previous element can appear more than once, and must be separated by a comma.